Graft copolymer, crosslinked particles, graft crosslinked particles, rubbery polymer, and thermoplastic resin composition using same

ABSTRACT

Provided is a graft copolymer that has an excellent impact-resistance-imparting effect and that can provide a thermoplastic resin composition excellent in weather resistance and color developability. A graft copolymer (C) obtained by graft-polymerizing one or two or more monomers (B), which are selected from (meth)acrylic acid esters, aromatic vinyls, vinyl cyanides, N-substituted maleimides, and maleic acid, onto a composite rubber-like polymer (A), which is obtained by polymerizing a mixture (Ac) containing a polyorganosiloxane (Aa) and an acrylic acid ester (Ab) after forming a miniemulsion in water solvent. A thermoplastic resin composition that contains the graft copolymer (C) and a thermoplastic resin (D).

TECHNICAL FIELD

The present invention relates to first to fourth inventions below.

The first invention relates to a graft polymer that has an excellentimpact-resistance-imparting effect and that can provide a thermoplasticresin composition excellent in weather resistance and colordevelopability, a production method thereof, a thermoplastic resincomposition including the graft copolymer, and a molded article thereof.

The second invention relates to crosslinked particles and graftcrosslinked particles that, as modifiers of a thermoplastic resin, canimprove the flowability, impact resistance, and abrasion resistance ofthe resin without impairing its color developability and mold shrinkagerate, a thermoplastic resin composition including the crosslinkedparticles and/or the graft crosslinked particles, and a molded articlethereof.

The third invention relates to crosslinked particles and graftcrosslinked particles that, as modifiers of a thermoplastic resin, canimprove the flowability, impact resistance, and abrasion resistance ofthe resin without impairing its color developability and weatherresistance, a thermoplastic resin composition including the crosslinkedparticles and/or the graft crosslinked particles, and a molded articlethereof.

The fourth invention relates to a rubbery polymer and a graft copolymerthat can provide a molded article excellent in impact resistance, colordevelopability, and molded appearance and production methods thereof.The fourth invention also relates to a thermoplastic resin compositionincluding the graft copolymer and a molded article thereof.

BACKGROUND ART Background Art of First Invention

Improving the impact resistance of a resin material offers very bigindustrial advantages such as widening the application of the materialand enabling slimming or upsizing of molded articles. Various techniquesfor improving the impact resistance of a resin material have beenstudied.

Conventionally, as a technique for improving the impact resistance of aresin material, incorporation of a graft polymer including a rubber-likepolymer as represented by an ABS resin into the resin material has beenknown.

ABS resins include diene rubber as a rubber component and thus have poorweather resistance, and outdoor use of resin materials reinforced withABS resins is limited. Various methods of incorporating a graft polymerhaving a rubber component other than diene rubber have been proposed.For example, the use of polyacrylic acid ester rubber,polyorganosiloxane, or polydimethylsiloxane-polyacrylic acid estercomposite rubber as a rubber component has been proposed. Of these,polydimethylsiloxane-acrylic acid ester composite rubber is veryexcellent in terms of the balance of impact resistance, weatherresistance, and economical efficiency.

Polydimethylsiloxane-polyacrylic acid ester composite rubber istypically produced by adding an acrylic acid ester to an emulsion ofpolydimethylsiloxane in one portion or multiple portions to causepolymerization (PTL 1).

This method generates not only polydimethylsiloxane-polyacrylic acidester composite rubber but also polydimethylsiloxane and polyacrylicacid ester that have not been combined together and does not readilyprovide polydimethylsiloxane-polyacrylic acid ester composite rubberhaving a uniform composition. A resin material including a graft polymerobtained using the resulting polydimethylsiloxane-polyacrylic acid estercomposite rubber has poor color developability due to the greatdifference in refractive index between polydimethylsiloxane andpolyacrylic acid ester.

In PTL 2, a thermoplastic resin composition whose color developabilityis improved by using polydimethylsiloxane-conjugated diene-acrylic acidester composite rubber is proposed. This thermoplastic resin compositionhas insufficient weather resistance because conjugated diene isincluded.

There has been a need for a graft copolymer that has an excellentimpact-resistance-imparting effect and that can provide a thermoplasticresin composition that is very excellent in weather resistance and colordevelopability.

Background Art of Second Invention

Thermoplastic resins such as styrene-acrylonitrile copolymer resins,α-methylstyrene-acrylonitrile copolymer resins, andstyrene-acrylonitrile-phenylmaleimide copolymer resins are widely usedas materials provided with impact resistance, which materials includegraft polymers obtained by graft-polymerizing monomers that impartcompatibility with these resins onto rubbery polymers and arerepresented by acrylonitrile-butadiene-styrene (ABS) resins,acrylonitrile-acrylic rubber-styrene (AAS) resins, etc.

ABS resins and AAS resins have poor abrasion resistance to soft clothssuch as gauze and cotton work gloves and are prone to wear.

As a resin that provides impact resistance and also has improvedabrasion resistance, an acrylonitrile-ethylene⋅α-olefin-styrene (AES)resin which includes ethylene⋅α-olefin rubber as a rubbery polymer isknown.

In PTL 3, a resin material for sliding that includes a rubber-toughenedstyrene resin such as an AES resin and an inorganic filler is proposed.However, AES resins include crystalline ethylene components and thushave mold shrinkage rates higher than those of ABS resins and otherresins, and when an AES resin is transferred to an existing mold usedfor ABS resins and other resins, a small molded article is provided. InPTL 3, the inorganic filler is included in a large amount, and thusimpact resistance is significantly reduced.

Background Art of Third Invention

Methacrylic resins, polycarbonate resins, polystyrene resins, alicyclicolefin polymers, etc. are known as transparent resins. These transparentresins are industrially mass-produced and are widely used in variousfields for their good transparency and color developability in the caseof being colored.

In interior and exterior parts applications, etc. in the automotivefield, etc., there has recently been a demand for being usable withoutpaint for a reduction in production cost. Accordingly, transparentresins that exhibit good color developability have increasingly beenapplied.

In particular, methacrylic resins among transparent resins havecharacteristics outstanding in optical properties such as transparencyand surface gloss, mechanical properties, scratch resistance, weatherresistance, etc. However, methacrylic resins are poor in impactresistance and abrasion resistance to soft materials such as gauze, andthus, when used without paint, the thickness of a molded article needsto be large. In addition, abrasions occur during assembling or carwashing.

As a method for improving the impact resistance and abrasion resistanceof a methacrylic resin, dispersion of a graft copolymer such as anacrylonitrile-ethylene⋅α-olefin-styrene (AES) resin in the methacrylicresin is known (PTL 4). This method improves impact resistance andabrasion resistance but reduces transparency and color developability inthe case of being colored.

A transparent acrylic film including a rubber-containing polymer made ofa specific monomer component is proposed (PTL 5). The impact resistanceand abrasion resistance provided by the rubber-containing polymerproposed here are insufficient.

Background Art of Fourth Invention

Thermoplastic resins such as styrene-acrylonitrile copolymer resins,α-methylstyrene-acrylonitrile copolymer resins, andstyrene-acrylonitrile-phenylmaleimide copolymer resins are widely usedas materials provided with impact resistance, which materials includegraft copolymers obtained by graft-polymerizing monomers that impartcompatibility with these resins onto rubbery polymers and arerepresented by ABS resins, ASA resins, etc. Of these, ASA resins, whichinclude, as a rubbery polymer, a component such as alkyl (meth)acrylaterubber which is saturated rubber, can provide good weather resistance.

However, ASA resins may disadvantageously result in poor appearance dueto, for example, a reduction in color developability of a colored moldedarticle or may provide low impact resistance. For the purpose ofimproving the balance between poor appearance and impact resistance, ASAresins composed of acrylic acid ester rubbery polymers in which rubberparticles having different particle size distributions are combined areproposed (PTLs 6 to 8).

To offset the disadvantages of ASA resins, a thermoplastic resincomposition in which an AES resin including an ethylene-propylene rubbercomponent and an ASA resin are used in combination is proposed (PTL 9).

The thermoplastic resin composition described above is insufficient inany of impact resistance, weather resistance, color developability, andmolded appearance and cannot sufficiently meet the recent strong need.

To improve impact resistance, a graft copolymer obtained by seededpolymerization using a rubber having a uniform particle size isproposed, but it is difficult to prepare rubber particles of 200 nm ormore, and the impact-resistance-improving effect is not sufficient (PTL10).

PTL 1: Japanese Patent Publication H1-190746 A

PTL 2: Japanese Patent Publication 2002-80684 A

PTL 3: Japanese Patent Publication 2011-178831 A

PTL 4: Japanese Patent Publication 2005-132970 A

PTL 5: Japanese Patent Publication 2012-144714 A

PTL 6: Japanese Patent Publication S59-232138 A

PTL 7: Japanese Patent Publication H04-225051 A

PTL 8: Japanese Patent Publication H08-134312 A

PTL 9: Japanese Patent Publication 2004-346187 A

PTL 10: Japanese Patent Publication 2000-344841 A

SUMMARY OF INVENTION

An object of the first invention is to provide a graft copolymer thathas an excellent impact-resistance-imparting effect and that can providea thermoplastic resin composition excellent in weather resistance andcolor developability, a production method thereof, a thermoplastic resincomposition including the graft copolymer, and a molded article thereof.

Inventors of the first invention have found that the problems describedabove can be solved by producing polyorganosiloxane-polyacrylic acidester composite rubber used for a graft copolymer by a specifictechnique.

The first invention is summarized as described below.

[1] A graft copolymer (C) obtained by graft-polymerizing one or two ormore monomers (B), which are selected from (meth)acrylic acid esters,aromatic vinyls, vinyl cyanides, N-substituted maleimides, and maleicacid, onto a composite rubber-like polymer (A), which is obtained bypolymerizing a mixture (Ac) containing a polyorganosiloxane (Aa) and anacrylic acid ester (Ab) after forming a miniemulsion in water solvent.

[2] The graft copolymer (C) according to [1], wherein thepolyorganosiloxane (Aa) has a refractive index of 1.470 to 1.600.

[3] The graft copolymer (C) according to [1] or [2], wherein thecomposite rubber-like polymer (A) has an average particle size of 10 to2000 nm.

[4] A method for producing the graft copolymer (C) according to any oneof [1] to [3], the method comprising: a step of miniemulsifying themixture (Ac) containing the polyorganosiloxane (Aa) and the acrylic acidester (Ab) in water solvent in the presence of a hydrophobic stabilizerand an emulsifier; and a step of polymerizing the resultingminiemulsion.

[5] A thermoplastic resin composition comprising: the graft copolymer(C) according to any one of [1] to [3]; and a thermoplastic resin (D).

[6] The thermoplastic resin composition according to [5], wherein arefractive index difference between the composite rubber-like polymer(A) in the graft copolymer (C) and the thermoplastic resin (D) is 0.02or less.

[7] A molded article obtained by molding the thermoplastic resincomposition according to [5] or [6].

An object of the second invention is to provide crosslinked particlesand graft crosslinked particles that, as modifiers of a thermoplasticresin, can improve the flowability, impact resistance, and abrasionresistance of the resin without impairing its color developability andmold shrinkage rate, a thermoplastic resin composition including thecrosslinked particles and/or the graft crosslinked particles, and amolded article thereof.

Inventors of the second invention have found that the above-describedproblems can be solved by crosslinked particles obtained bypolymerization using a di(meth)acrylic acid ester having a specificmolecular weight as a crosslinking agent and, furthermore, by graftcrosslinked particles obtained by graft-polymerizing a monomer onto thecrosslinked particles.

The second invention is summarized as described below.

[8] Crosslinked particles (A-I) obtained by polymerizing a monomermixture (i-I) containing a di(meth)acrylic acid ester (a) having anumber average molecular weight (Mn) of 800 to 9,000 and represented byformula (1):

wherein X represents a divalent residue constituted by at least one diolselected from polyalkylene glycols, polyester diols, and polycarbonatediols, and R^(1a) and R^(1b) each independently represent H or CH₃.

[9] The crosslinked particles (A-I) according to [8], wherein the X is apolytetramethylene glycol residue.

[10] The crosslinked particles (A-I) according to [8] or [9], wherein acontent of the di(meth)acrylic acid ester (a) in the monomer mixture(i-I) is 0.1% to 90% by mass.

[11] The crosslinked particles (A-I) according to any one of [8] to[10], wherein the monomer mixture (i-I) contains the di(meth)acrylicacid ester (a), an aromatic vinyl (b), and a vinyl cyanide (c), and aproportion of the aromatic vinyl (b) in 100% by mass of a total of thearomatic vinyl (b) and the vinyl cyanide (c) is 60% to 90% by mass.

[12] The crosslinked particles (A-I) according to any one of [8] to[11], wherein the crosslinked particles (A-I) have an average particlesize of 0.07 to 5.0 μm.

[13] A method for producing the crosslinked particles (A-I) according toany one of [8] to [12], the method comprising: a step of miniemulsifyingthe monomer mixture (i-I) containing the di(meth)acrylic acid ester (a)in water solvent in the presence of a hydrophobic stabilizer and anemulsifier; and a step of polymerizing the resulting miniemulsion.

[14] Graft crosslinked particles (B-I) obtained by graft-polymerizing amonomer onto the crosslinked particles (A-I) according to any one of [8]to [12].

[15] The graft crosslinked particles (B-I) according to [14], whereinthe graft crosslinked particles (B-I) are obtained by graft-polymerizing10% to 60% by mass of the monomer onto 40% to 90% by mass of thecrosslinked particles (A-I) (provided that a total amount of thecrosslinked particles (A-I) and the monomer is 100% by mass), themonomer includes at least an aromatic vinyl and a vinyl cyanide, and aproportion of the aromatic vinyl in 100% by mass of a total of thearomatic vinyl and the vinyl cyanide is 60% to 99% by mass.

[16] The graft crosslinked particles (B-I) according to [14] or [15],wherein the graft crosslinked particles (B-I) have a graft rate of 23%to 100%.

[17] A thermoplastic resin composition comprising: the crosslinkedparticles (A-I) according to any one of [8] to [12] and/or the graftcrosslinked particles (B-I) according to any one of claims 14 to 16; anda thermoplastic resin (D-I).

[18] A molded article obtained by molding the thermoplastic resincomposition according to [17].

An object of the third invention is to provide crosslinked particles andgraft crosslinked particles that, as modifiers of a thermoplastic resin,can improve the flowability, impact resistance, and abrasion resistanceof the resin without impairing its color developability and weatherresistance, a thermoplastic resin composition including the crosslinkedparticles and/or the graft crosslinked particles, and a molded articlethereof.

Inventors of the third invention have found that the above-describedproblems can be solved by crosslinked particles obtained bypolymerization using a di(meth)acrylic acid ester having a specificmolecular weight as a crosslinking agent and, furthermore, by graftcrosslinked particles obtained by graft-polymerizing a monomer onto thecrosslinked particles.

The third invention is summarized as described below.

[19] Crosslinked particles (A-II) having a volume average particle sizeof 0.07 to 2.0 μm and obtained by polymerizing a monomer mixture (i-II)containing a di(meth)acrylic acid ester (a) and a mono(meth)acrylic acidcomponent (d), wherein a content of the di(meth)acrylic acid ester (a)in 100% by mass of the monomer mixture (i-II) is 20% to 80% by mass, thedi(meth)acrylic acid ester (a) having a number average molecular weightof 800 to 9,000 and being represented by formula (1):

wherein X represents a divalent residue constituted by at least one diolselected from polyalkylene glycols, polyester diols, and polycarbonatediols, and R^(1a) and R^(1b) each independently represent H or CH₃.

[20] The crosslinked particles (A-II) according to [19], wherein themonomer mixture (i-II) contains at least styrene as an additional vinylcompound (e).

[21] The crosslinked particles (A-II) according to [19] or [20], whereinthe X is a polytetramethylene glycol residue.

[22] The crosslinked particles (A-II) according to any one of [19] to[21], wherein a content of the mono(meth)acrylic acid ester (d) in themonomer mixture (i-II) is 1% to 80% by mass.

[23] A method for producing the crosslinked particles (A-II) accordingto any one of [19] to [22], the method comprising: a step ofminiemulsifying the monomer mixture (i-II) containing thedi(meth)acrylic acid ester (a) and the mono(meth)acrylic acid component(d) in water solvent in the presence of a hydrophobic stabilizer and anemulsifier; and a step of polymerizing the resulting miniemulsion.

[24] Graft crosslinked particles (B-II) obtained by graft-polymerizingone or more monomers selected from (meth)acrylic acid esters, aromaticvinyls, vinyl cyanides, maleimides, and maleic anhydride onto thecrosslinked particles (A-II) according to any one of [19] to [22].

[25] The graft crosslinked particles (B-II) according to [24], whereinthe graft crosslinked particles (B-II) are obtained bygraft-polymerizing 10% to 60% by mass of the monomer onto 40% to 90% bymass of the crosslinked particles (A-II) (provided that a total amountof the crosslinked particles (A-II) and the monomer is 100% by mass),the monomer includes at least methyl methacrylate and methyl acrylate,and a proportion of the methyl methacrylate in 100% by mass of a totalof the methyl methacrylate and the methyl acrylate is 90% to 99.9% bymass.

[26] The graft crosslinked particles (B-II) according to [24] or [25],wherein the graft crosslinked particles (B-II) have a graft rate of 23%to 100%.

[27] A thermoplastic resin composition comprising: the crosslinkedparticles (A-II) according to any one of [19] to 22 and/or the graftcrosslinked particles (B-II) according to any one of [23] to [26]; and athermoplastic resin (D-II).

[28] A molded article obtained by molding the thermoplastic resincomposition according to [27].

An object of the fourth invention is to provide a rubbery polymer and agraft copolymer that can provide a thermoplastic resin molded articleexcellent in impact resistance, color developability, and moldedappearance, production methods thereof, a thermoplastic resincomposition including the graft copolymer, and a molded article thereof.

Inventors of the fourth invention have found that the above object canbe achieved by a graft copolymer obtained using a rubbery polymerobtained by miniemulsion polymerization of a mixture containing an alkyl(meth)acrylate, a hydrophobe, and an emulsifier.

The fourth invention is summarized as described below.

[29] A rubbery polymer (A-III) that is a miniemulsion polymerizationreaction product of an alkyl (meth)acrylate.

[30] The rubbery polymer (A-III) according to [29], wherein the rubberypolymer (A-III) is a miniemulsion polymerization reaction product of amixture (i-III) containing an alkyl (meth)acrylate, a hydrophobe, and anemulsifier.

[31] The rubbery polymer (A-III) according to [30], wherein the mixture(i-III) further contains a crosslinking agent.

[32] The rubbery polymer (A-III) according to any one of [29] to [31],wherein when an average particle size (X) is represented by X; a largest10% frequency particle size (Y), which is a particle size at which acumulative frequency from a largest value in a particle sizedistribution curve reaches 10%, is represented by Y; and a smallest 10%frequency particle size (Z), which is a particle size at which acumulative frequency from a smallest value in the particle sizedistribution curve reaches 10%, is represented by Z, the averageparticle size (X), the largest 10% frequency particle size (Y), and thesmallest 10% frequency particle size (Z) satisfy (2) or (3) below:

(2) The average particle size (X) satisfies X≤300 nm, the largest 10%frequency particle size (Y) satisfies Y≤1.6X, and the smallest 10%frequency particle size (Z) satisfies Z≥0.7X; or

(3) The average particle size (X) satisfies X=300 to 800 nm, the largest10% frequency particle size (Y) satisfies Y≤1.7X, and the smallest 10%frequency particle size (Z) satisfies Z≥0.6X.

[33] A graft copolymer (B-III) comprising: the rubbery polymer (A-III)according to any one of [29] to [32]; and at least one monomer selectedfrom aromatic vinyl compounds, (meth)acrylic acid esters, and vinylcyanide compounds graft-polymerized onto the rubbery polymer (A-III).

[34] A method for producing the rubbery polymer (A-III) according to anyone of [29] to [32], the method comprising: a step of miniemulsifyingthe mixture (i-III) containing an alkyl (meth)acrylate, a hydrophobe,and an emulsifier; and a step of polymerizing the resultingminiemulsion.

[35] A method for producing the graft copolymer (B-III) according to[33], the method comprising: a step of miniemulsifying the mixture(i-III) containing an alkyl (meth)acrylate, a hydrophobe, and anemulsifier; a step of polymerizing the resulting miniemulsion; and astep of graft-polymerizing at least one monomer selected from aromaticvinyl compounds, (meth)acrylic acid esters, and vinyl cyanide compoundsonto the resulting rubbery polymer (A-III).

[36] A thermoplastic resin composition comprising the graft copolymer(B-III) according to [33].

[37] A molded article obtained by molding the thermoplastic resincomposition according to [36].

Advantageous Effects of Invention

By incorporating the graft copolymer of the first invention into athermoplastic resin, a thermoplastic resin composition excellent inweather resistance and color developability as well as in impactresistance and a molded article thereof can be achieved.

According to the crosslinked particles and the graft crosslinkedparticles of the second invention, the flowability, impact resistance,and abrasion resistance of a thermoplastic resin can be improved withoutimpairing its color developability and mold shrinkage rate, and athermoplastic resin composition excellent in flowability, colordevelopability, dimensional stability, shape accuracy, impactresistance, and abrasion resistance and a molded article thereof can beprovided.

According to the crosslinked particles and the graft crosslinkedparticles of the third invention, the flowability, impact resistance,and abrasion resistance of a thermoplastic resin can be improved withoutimpairing its color developability and weather resistance, and athermoplastic resin composition excellent in all characteristics:flowability, color developability, weather resistance, impactresistance, and abrasion resistance, and a molded article thereof can beprovided.

According to the rubbery polymer and the graft copolymer of the fourthinvention, a thermoplastic resin composition and a molded article thatare excellent in impact resistance, molded appearance, and colordevelopability can be provided.

BRIEF DESCRIPTION OF DRAWING

FIG. 1 illustrates a method for evaluating abrasion resistance inEXAMPLES.

DESCRIPTION OF EMBODIMENTS

An embodiment of the first invention will now be described in detail.

In this description, “(meth)acrylic” means one or both of “acrylic” and“methacrylic”. The same applies to “(meth)acrylate”.

“Molded article” means a substance obtained by molding a thermoplasticresin composition.

Embodiment of First Invention [Graft Copolymer (C)]

A graft copolymer (C) of the first invention is obtained bygraft-polymerizing one or two or more monomers (B) selected from(meth)acrylic acid esters, aromatic vinyls, vinyl cyanides,N-substituted maleimides, and maleic acid onto a composite rubber-likepolymer (A) (hereinafter also referred to as “the composite rubber-likepolymer (A) of the first invention”) obtained by miniemulsifying amixture (Ac) containing a polyorganosiloxane (Aa) and an acrylic acidester (Ab) in water solvent and then polymerizing the polyorganosiloxane(Aa) and the acrylic acid ester (Ab) in the miniemulsion.

By polymerizing the mixture (Ac) of the polyorganosiloxane (Aa) and theacrylic acid ester (Ab) after being miniemulsified, the composition ofeach of the resulting composite rubber-like polymer (A) particles tendsto be uniform. A thermoplastic resin composition obtained byincorporating the graft copolymer (C) produced using the compositerubber-like polymer (A) has improved color developability.

In commonly used emulsion polymerization in which the mixture (Ac) and aradical initiator are added in the presence of water solvent and anemulsifier to cause polymerization and in seeded polymerization asdescribed in PTL 1 in which an acrylic acid ester is added in thepresence of an emulsion of a polyorganosiloxane to cause polymerization,the composition of composite rubber-like polymer particles is unlikelyto be uniform, and, in some cases, particles of the polyorganosiloxanealone or of the polyacrylic acid ester alone are formed. A graftcopolymer obtained using such a composite rubber-like polymer provides athermoplastic resin composition having poor color developability.

The first invention is characterized by producing the compositerubber-like polymer (A) by a miniemulsion polymerization methodincluding two steps: a step of miniemulsifying the mixture (Ac) of thepolyorganosiloxane (Aa) and the acrylic acid ester (Ab) and a subsequentpolymerization step.

<Composite Rubber-Like Polymer (A)>

The composite rubber-like polymer (A) of the first invention is obtainedby polymerizing the mixture (Ac) containing the polyorganosiloxane (Aa)and the acrylic acid ester (Ab) after forming a miniemulsion in watersolvent.

<<Polyorganosiloxane (Aa)>>

The polyorganosiloxane (Aa) in the first invention is a polymer whosemain chain is a siloxane unit which is a silicon-oxygen bond, and thepolyorganosiloxane (Aa) has two organic groups (including hydrogenatoms) on a silicon atom.

Examples of the organic groups on the silicon atom of thepolyorganosiloxane (Aa) include, but are not limited to, a hydrogenatom, an alkyl group, an aryl group, a vinyl group, an amino group, anepoxy group, an alicyclic epoxy group, a mercapto group, and a carboxylgroup. As the organic groups, alkyl groups having 1 to 6 carbon atoms, avinyl group, and an aryl group are particularly preferred. Thepolyorganosiloxane (Aa) may have only one of these organic groups or mayhave two or more of them.

The viscosity of the polyorganosiloxane (Aa) is not particularly limitedas long as the mixture (Ac) can be obtained by mixing thepolyorganosiloxane (Aa) with the acrylic acid ester (Ab). When theviscosity of the polyorganosiloxane (Aa) is oily, such as 10 to 10000mm²/s, preferably 100 to 5000 mm²/s, the production stability of thecomposite rubber-like polymer (A) tends to be excellent. The viscosityof the polyorganosiloxane (Aa) is a value measured at 25° C. using akinematic viscometer.

The refractive index of the polyorganosiloxane (Aa) is not particularlylimited but preferably in the range of 1.470 to 1.600 for the followingreasons. When the graft copolymer (C) of the first invention isincorporated into a thermoplastic resin (D) to obtain a thermoplasticresin composition, the thermoplastic resin composition obtained has goodcolor developability if the refractive index of the thermoplastic resin(D) and the refractive index of the composite rubber-like polymer (A) inthe graft copolymer (C) close to each other. The refractive index of thebelow-described thermoplastic resin (D) used for a thermoplastic resincomposition of the first invention is in the range of 1.470 to 1.600 inmany cases. Therefore, the refractive index of the polyorganosiloxane(Aa) is preferably in the range of 1.470 to 1.600. Although it depends,for example, on the conditions for producing the composite rubber-likepolymer (A), when the refractive index of the polyorganosiloxane (Aa) isin the range of 1.470 to 1.600, the composite rubber-like polymer (A)having a refractive index of about 1.460 to 1.590, which is close to therefractive index of the thermoplastic resin (D), can be produced.

When the difference in refractive index between the compositerubber-like polymer (A) of the first invention and the thermoplasticresin (D) is 0.02 or less and the thermoplastic resin (D) hastransparency, a thermoplastic resin composition having particularly goodcolor developability is provided, and, in addition, the transparency ofthe thermoplastic resin composition also tends to be high unless a coloris imparted, for example, by the blending of a colorant. Also for thereason that the difference in refractive index between the compositerubber-like polymer (A) and the thermoplastic resin (D) is likely to be0.02 or less, the refractive index of the polyorganosiloxane (Aa) ispreferably 1.470 to 1.600.

When the polyorganosiloxane (Aa) has one or more aryl groups as organicgroups, the refractive index of the polyorganosiloxane (Aa) tends to bein the range of 1.470 to 1.600.

Examples of aryl groups include a phenyl group, a naphthyl group, analkyl nuclear-substituted phenyl group, an alkyl nuclear-substitutednaphthyl group, a halogen nuclear-substituted phenyl group, and ahalogen nuclear-substituted naphthyl group, and preferred are a phenylgroup and a nuclear-substituted phenyl group. Examples of alkyl groupsof the alkyl nuclear-substituted phenyl group and the alkylnuclear-substituted naphthyl group include alkyl groups having 1 to 12carbon atoms.

Examples of the polyorganosiloxane (Aa) having an aryl group includeindustrially available products such as “KF-53”, “KF-54”, “X-21-3265”,“KF-54SS”, “KF-56”, “HIVAC-F-4”, and “HIVAC-F-5” available fromShin-Etsu Chemical Co., Ltd.

The refractive index of the polyorganosiloxane (Aa) can be measuredsimilarly to the refractive index of the composite rubber-like polymer(A), which will be described in the section of EXAMPLES below. Forcommercially available products, catalogue values can be employed.

The polyorganosiloxane (Aa) may be used alone or as a mixture of two ormore.

<<Acrylic Acid Ester (Ab)>>

Examples of the acrylic acid ester (Ab) in the first invention includeacrylic acid alkyl esters having alkyl groups of 1 to 12 carbon atoms;and acrylic acid aryl esters having aromatic hydrocarbon groups such asa phenyl group and a benzyl group. The alkyl groups of the acrylic acidalkyl esters and the aryl groups of the acrylic acid aryl ester may besubstituted with substituents such as a hydroxyl group.

Specific examples of the acrylic acid ester (Ab) include methylacrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butylacrylate, i-butyl acrylate, t-butyl acrylate, amyl acrylate, isoamylacrylate, octyl acrylate, 2-ethylhexyl acrylate, decyl acrylate, laurylacrylate, stearyl acrylate, lauryl acrylate, stearyl acrylate,cyclohexyl acrylate, pentyl acrylate, phenyl acrylate, benzyl acrylate,2-hydroxyethyl acrylate, and 2-hydroxypropyl acrylate. Of these, n-butylacrylate, 2-ethylhexyl acrylate, and ethyl acrylate are preferred.

The acrylic acid ester (Aa) may be used alone or as a mixture of two ormore.

The amount of the acrylic acid ester (Ab) used in the production of thecomposite rubber-like polymer (A) of the first invention is preferably10% to 99% by mass, particularly preferably 20% to 95% by mass, relativeto 100% by mass of the total of the polyorganosiloxane (Aa) and theacrylic acid ester (Ab). When the amount of the acrylic acid ester (Ab)used is in the above range, the thermoplastic resin composition obtainedby incorporating the graft copolymer (C) of the first invention isprovided with good color developability and good impact resistance.

<Polyfunctional Compound>

A polyfunctional compound may optionally be added to the mixture (Ac)containing the polyorganosiloxane (Aa) and the acrylic acid ester (Ab)used to produce the composite rubber-like polymer (A) of the firstinvention. Due to the addition of a polyfunctional compound, thethermoplastic resin composition obtained by incorporating the graftcopolymer (C) of the first invention is provided with good colordevelopability and good impact resistance.

The polyfunctional compound has two or more carbon-carbon double bondsin its molecule and is not particularly limited. Examples ofpolyfunctional compounds include divinylbenzene, allyl (meth)acrylate,ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate,1,3-butylene di(meth)acrylate, 1,4-butylene glycol di(meth)acrylate,tetraethylene glycol di(meth)acrylate, tetradecaethylene glycoldi(meth)acrylate, triallyl cyanurate, triallyl isocyanurate, andpentaerythritol tetra(meth)acrylate.

The polyfunctional compounds may be used alone or in a combination oftwo or more.

The polyfunctional compound can be used so as to replace part of theacrylic acid ester (Ab) in the mixture (Ac) containing thepolyorganosiloxane (Aa) and the acrylic acid ester (Ab). Thepolyfunctional compound is preferably added so as to replace 0.1% to 5%by mass, particularly 0.2% to 3% by mass, and especially 0.5% to 2% bymass of the acrylic acid ester (Ab) (100% by mass) since thethermoplastic resin composition obtained by incorporating the graftcopolymer (C) of the first invention is provided with good impactresistance.

<<Method for Producing Composite Rubber-Like Polymer (A)>>

The composite rubber-like polymer (A) of the first invention is obtainedby what is called miniemulsion polymerization in which the mixture (Ac)containing the polyorganosiloxane (Aa), the acrylic acid ester (Ab), andoptionally a polyfunctional compound is sheared in water solvent in thepresence of an emulsifier, preferably in the presence of an emulsifierand a hydrophobic stabilizer, to form a miniemulsion and then theminiemulsion is copolymerized in the presence of a radical initiator.The radical initiator may be added before or after the miniemulsion isformed and may be added in one portion, in multiple portions, or in acontinuous manner.

From the viewpoint of workability, stability, production efficiency,etc., the amount of water solvent used in the miniemulsification ispreferably about 100 to 500 parts by mass relative to 100 parts by massof the mixture (Ac).

As a method for applying shear in forming the miniemulsion, any knownmethod can be used. The shear may be applied in one portion, in multipleportions, in a continuous manner, or in a circular manner. In general,the miniemulsion can be formed by using a high shear device that formsdroplets having diameters of about 10 to 2000 nm.

Examples of usable high shear devices that form miniemulsions include,but are not limited to, emulsification devices including high-pressurepumps and interaction chambers and devices that form miniemulsions withultrasonic energy or a high frequency. Examples of emulsificationdevices including high-pressure pumps and interaction chambers include“Microfluidizer” available from Powrex corp. Examples of devices thatform miniemulsions with ultrasonic energy or a high frequency include“Sonic Dismembrator” available from Fisher Scient and “ULTRASONICHOMOGENIZER” available from Nihonseiki Kaisha Ltd.

Examples of emulsifiers include anionic surfactants, nonionicsurfactants, and amphoteric surfactants. Examples of emulsifiers includeanionic surfactants such as sulfates of higher alcohols, alkylbenzenesulfonates, fatty acid sulfonates, phosphates (e.g., ammoniummonoglyceride phosphate), fatty acid salts (e.g., dipotassium alkenylsuccinate), and salts of amino acid derivatives; commonly used nonionicsurfactants such as alkyl-ester-type polyethylene glycol surfactants,alkyl-ether-type polyethylene glycol surfactants, andalkylphenyl-ether-type polyethylene glycol surfactants; and amphotericsurfactants having carboxylates, sulfates, sulfonates, phosphates, andthe like as anionic moieties and amine salts, quarternary ammoniumsalts, and the like as cationic moieties. The emulsifiers may be usedalone or in a combination of two or more.

The addition amount of emulsifier is typically 10 parts by mass or less,preferably, for example, 0.01 to 10 parts by mass, relative to 100 partsby mass of the mixture (Ac).

When the miniemulsion is formed, adding a hydrophobic stabilizer tendsto further improve the production stability of the miniemulsion.Examples of hydrophobic stabilizers include unpolymerizable hydrophobiccompounds, for example, hydrocarbons having 10 to 30 carbon atoms,alcohols having 10 to 30 carbon atoms, hydrophobic polymers having massaverage molecular weights (Mw) of less than 10000, tetraalkylsilanes,hydrophobic monomers, for example, vinyl esters of alcohols having 10 to30 carbon atoms, carboxylic acid vinyl esters having 10 to 30 carbonatoms, (meth)acrylic acid esters having 8 to 30 carbon atoms,p-alkylstyrenes, hydrophobic chain transfer agents, and hydrophobicperoxides. The hydrophobic stabilizers may be used alone or as a mixtureof two or more.

Specific examples of the hydrophobic stabilizer include decane,undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane,olive oil, polystyrenes having mass average molecular weights (Mw) of500 to 5000, siloxanes having mass average molecular weights (Mw) of 500to 5000, cetyl alcohol, stearyl alcohol, palmityl alcohol, behenylalcohol, p-methylstyrene, 2-ethylhexyl acrylate, decyl acrylate, stearylacrylate, lauryl methacrylate, stearyl methacrylate, lauryl mercaptan(normal dodecyl mercaptan), and hydrophobic peroxides such as lauroylperoxide.

When a hydrophobic stabilizer is used, the amount thereof is preferably0.05 to 5 parts by mass relative to 100 parts by mass of the mixture(Ac). When the addition amount of hydrophobic stabilizer is not lessthan the above lower limit, the production stability of the compositerubber-like polymer (A) can be further improved. When the additionamount of hydrophobic stabilizer is not more than the above upper limit,there is a tendency that the color developability and impact resistanceof a thermoplastic resin composition obtained by incorporating the graftcopolymer (C) of the first invention can be good.

As a radical initiator used in the polymerization step subsequent to theminiemulsification step, a known one can be used. Examples of radicalinitiators include azo polymerization initiators, photopolymerizationinitiators, inorganic peroxides, organic peroxides, and redox initiatorscontaining organic peroxides, transition metals, and reducing agents incombination. Of these, azo polymerization initiators, inorganicperoxides, organic peroxides, and redox initiators, which are capable ofinitiating polymerization upon heating, are preferred. The radicalinitiators may be used alone or in a combination of two or more.

Examples of azo polymerization initiators include2,2′-azobis(4-methoxy-2,4-dimethylvaleronitrile),2,2′-azobis(2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile,2,2′-azobis(2-methylbutyronitrile),1,1′-azobis(cyclohexane-1-carbonitrile),1-[(1-cyano-1-methylethyl)azo]formamide, 4,4′-azobis(4-cyanovalericacid), dimethyl 2,2′-azobis(2-methyl propionate), dimethyl1,1′-azobis(1-cychloexanecarboxylate),2,2′-azobis[2-methyl-N-(2-hydroxyethyl)propionamide],2,2′-azobis(N-butyl-2-methylpropionamide),2,2′-azobis(N-cyclohexyl-2-methylpropionamide),2,2′-azobis[2-(2-imidazolin-2-yl)propane], and2,2′-azobis(2,4,4-trimethylpentane).

Examples of inorganic peroxides include potassium persulfate, sodiumpersulfate, ammonium persulfate, and hydrogen peroxide.

Examples of organic peroxides include peroxyester compounds. Specificexamples thereof include α,α′-bis(neodecanoylperoxy)diisopropylbenzene,cumyl peroxyneodecanoate, 1,1,3,3-tetramethylbutyl peroxyneodecanoate,1-cyclohexyl-1-methylethyl peroxyneodecanoate, t-hexylperoxyneodecanoate, t-butyl peroxyneodecanoate, t-hexyl peroxypivalate,t-butyl peroxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate,2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane,1-cyclohexyl-1-methylethyl peroxy-2-ethylhexanoate, t-hexylperoxy-2-hexylhexanoate, t-butyl peroxy-2-hexylhexanoate, t-butylperoxyisobutyrate, t-hexyl peroxyisopropylmonocarbonate, t-butylperoxymaleic acid, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, 2,5-dimethyl-2,5-bis(m-toluoylperoxy)hexane, t-butylperoxyisopropylmonocarbonate, t-butyl peroxy-2-ethylhexylmonocarbonate,t-hexyl peroxybenzoate, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane,t-butyl peroxyacetate, t-butyl peroxy-m-toluoylbenzoate, t-butylperoxybenzoate, bis(t-butylperoxy) isophthalate,1,1-bis(t-hexylperoxy)3,3,5-trimethylcyclohexane,1,1-bis(t-hexylperoxy)cyclohexane,1,1-bis(t-butylperoxy)3,3,5-trimethylcyclohexane,1,1-bis(t-butylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)cyclododecane,2,2-bis(t-butylperoxy)butane, n-butyl 4,4-bis(t-butylperoxy)valerate,2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane,α,α′-bis(t-butylperoxide)diisopropylbenzene, dicumyl peroxide,2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, t-butyl cumyl peroxide,di-t-butylperoxide, cumene hydroperoxide, diisopropylbenzenehydroperoxide, t-butyl hydroperoxide, benzoyl peroxide, lauroylperoxide, dimethylbis(t-butylperoxy)hexyne-3,bis(t-butylperoxyisopropyl)benzene,bis(t-butylperoxy)trimethylcyclohexane, butyl-bis(t-butylperoxy)valerate, t-butyl peroxy-2-ethylhexanoate, dibenzoyl peroxide,paramenthane hydroperoxide, and t-butyl peroxybenzoate.

As a redox initiator, a combination of an organic peroxide, ferroussulfate, a chelating agent, and a reducing agent is preferred. Examplesinclude a combination of cumene hydroperoxide, ferrous sulfate, sodiumpyrophosphate, and dextrose and a combination of t-butyl hydroperoxide,sodium formaldehyde sulfoxylate (Rongalite), ferrous sulfate, anddisodium ethylenediaminetetraacetate.

The addition amount of radical initiator is typically 5 parts by mass orless, preferably 3 parts by mass or less, for example 0.001 to 3 partsby mass, relative to 100 parts by mass of the acrylic acid ester (Ab)(in the case where a polyfunctional compound is used, the total of theacrylic acid ester (Ab) and the polyfunctional compound). As describedabove, the radical initiator may be added before or after theminiemulsion is formed and may be added in one portion, in multipleportions, or in a continuous manner.

In the production of the composite rubber-like polymer (A), a chaintransfer agent may optionally be added. Examples of chain transferagents include mercaptans (e.g., octyl mercaptan, n- or t-dodecylmercaptan, n-hexadecyl mercaptan, n- or t-tetradecyl mercaptan), allylcompounds (allyl sulfonic acid, methallyl sulfonic acid, and sodiumsalts thereof), and α-methylstyrene dimers. The chain transfer agentsmay be used alone or in a combination of two or more. Preferred chaintransfer agents are mercaptans in terms of ease of control of molecularweight.

When a chain transfer agent is used, it may be added in one portion, inmultiple portions, or in a continuous manner. The addition amount ofchain transfer agent is typically 2.0 parts by mass or less, preferably,for example, 0.01 to 2.0 parts by mass, relative to 100 parts by mass ofthe acrylic acid ester (Ab) (in the case where a polyfunctional compoundis used, the total of the acrylic acid ester (Ab) and the polyfunctionalcompound).

The polymerization step subsequent to the miniemulsification step istypically performed at 40° C. to 95° C. for about 0.5 to 8 hoursfollowing the miniemulsification step.

The particle size (average particle size) of the composite rubber-likepolymer (A) of the first invention produced through the above-describedminiemulsification step and the subsequent polymerization step ispreferably 10 to 2000 nm, more preferably 60 to 1000 nm, particularlypreferably 80 to 600 nm. When the particle size of the compositerubber-like polymer (A) is in the above range, the thermoplastic resincomposition obtained by incorporating the graft copolymer (C) of thefirst invention tends to have good impact resistance.

The particle size of the composite rubber-like polymer (A) may becontrolled by any method, for example, by adjusting the type or amountof emulsifier used and the shear force during the production of theminiemulsion.

Specifically, the average particle size of the composite rubber-likepolymer (A) is measured by the method described in the section ofEXAMPLES below.

<Monomer (B)>

The graft copolymer (C) of the first invention is obtained bygraft-polymerizing a monomer (B) onto the composite rubber-like polymer(A) produced as described above.

The monomer (B) is one or two or more selected from (meth)acrylic acidesters, aromatic vinyls, vinyl cyanides, N-substituted maleimides, andmaleic acid. The monomer (B) can be selected according to thecompatibility with the thermoplastic resin (D) described below or to theintended use. For example, the use of an aromatic vinyl tends to providegood moldability. The use of a vinyl cyanide can improve chemicalresistance, impact resistance, and compatibility with the thermoplasticresin (D) having polarity. The use of a methacrylic acid ester canprovide a molded article with improved surface hardness and surfaceappearance. The use of an N-substituted maleimide can improve heatresistance.

Examples of (meth)acrylic acid esters include methyl (meth)acrylate,ethyl (meth)acrylate, n-propyl (meth)acrylate, 1-propyl (meth)acrylate,n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate,amyl (meth)acrylate, isoamyl (meth)acrylate, octyl (meth)acrylate,2-ethylhexyl (meth)acrylate, decyl (meth)acrylate, lauryl(meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, andphenyl (meth)acrylate.

Examples of aromatic vinyls include styrene, α-methylstyrene, o-, m-, orp-methylstyrene, vinyl xylene, p-t-butylstyrene, and ethylstyrene.

Examples of vinyl cyanides include acrylonitrile and methacrylonitrile.

Examples of N-substituted maleimides include N-cyclohexylmaleimide andN-phenylmaleimide.

Examples of maleic acid include maleic acid and maleic anhydride.

When a combination of a methacrylic acid ester and an acrylic acid esteris used as the monomer (B), better results in terms of thermal stabilityare obtained as compared to when a methacrylic acid ester is used alone.In this case, it is preferable to use the methacrylic acid ester in anamount of 70% to 99.5% by mass and the acrylic acid ester in an amountof 0.5% to 30% by mass (provided that the total amount of themethacrylic acid ester and the acrylic acid ester is 100% by mass).

When a combination of an aromatic vinyl and a vinyl cyanide is used asthe monomer (B), better results in terms of compatibility with thethermoplastic resin (D) are obtained. In this case, it is preferable touse the aromatic vinyl in an amount of 60% to 99% by mass and the vinylcyanide in an amount of 1% to 40% by mass (provided that the totalamount of the aromatic vinyl and the vinyl cyanide is 100% by mass).

The proportions of the composite rubber-like polymer (A) and the monomer(B) used in graft polymerization are not particularly limited, but, ingeneral, the proportion of the composite rubber-like polymer (A) is 10%to 80% by mass, preferably 40% to 75% by mass, and the proportion of themonomer (B) is 20% to 90% by mass, preferably 25% to 60% by mass(provided that the total amount of the composite rubber-like polymer (A)and the monomer (B) is 100% by mass). When the proportions of thecomposite rubber-like polymer (A) and the monomer (B) are in the aboveranges, productivity and impact resistance of the graft copolymer (C)are good, and, in addition, the color developability and impactresistance of a thermoplastic resin composition obtained byincorporating the graft copolymer (C) and a molded article thereof tendto improve.

<Method for Producing Graft Copolymer (C)>

The method for graft-polymerizing the monomer (B) onto the compositerubber-like polymer (A) is not particularly limited. Since the compositerubber-like polymer (A) is prepared by miniemulsion polymerization andprovided in the form of emulsified latex, the graft polymerization ispreferably carried out also by emulsion polymerization. Examples ofemulsion graft polymerization include a method in which the monomer (B)is added in one portion, in a continuous manner, or in an intermittentmanner in the presence of an emulsion of the composite rubber-likepolymer (A) to cause radical polymerization. In the graftpolymerization, a chain transfer agent for molecular weight adjustmentand graft rate control, a known inorganic electrolyte for adjusting theviscosity and pH of latex, etc. can be used. The type and additionamount of these are not particularly limited. In the emulsion graftpolymerization, various emulsifiers can be used as required. As a chaintransfer agent, emulsifier, and radical initiator, for example, thoseexemplified as those used in the production of the composite rubber-likepolymer (A) can be used.

The method for obtaining the graft copolymer (C) in the form of granulesfrom the emulsion of the graft copolymer (C) produced as described aboveis not particularly limited. Examples include a method in which theemulsion is put in hot water containing a dissolved coagulant andallowed to coagulate and solidify and a spray drying method. Examples ofusable coagulants include inorganic acids such as sulfuric acid,hydrochloric acid, phosphoric acid, and nitric acid and metal salts suchas calcium chloride, calcium acetate, and aluminum sulfate.

[Thermoplastic Resin Composition]

The thermoplastic resin composition of the first invention includes thegraft copolymer (C) of the first invention and the thermoplastic resin(D).

<Thermoplastic Resin (D)>

Examples of the thermoplastic resin (D) in the first invention include,but are not limited to, acrylic resins (PMMA), acrylonitrile-styrenecopolymers (AS resins), polycarbonate resins, polybutylene terephthalate(PBT resins), methyl methacrylate-styrene copolymer resins (MS resins),polyethylene terephthalate (PET resins), polyvinyl chloride,polystyrene, polyacetal resins, modified polyphenylene ethers (modifiedPPE resins), ethylene-vinyl acetate copolymers, polyarylate, liquidcrystal polyester resins, polyethylene resins, polypropylene resins,fluorocarbon resins, and polyamide resins (nylon).

The thermoplastic resin (D) may be used alone or as a mixture of two ormore.

When a transparent resin among them is used, using a transparent resinhaving a refractive index different from that of the compositerubber-like polymer (A) in the thermoplastic resin (D) by 0.02 or lessnot only provides particularly good color developability but alsoprovides a thermoplastic resin composition also having high transparencyunless colored. The refractive index difference is preferably as smallas possible, more preferably 0.01 or less.

Examples of transparent resins include, but are not limited to, acrylicresins (refractive index: 1.48 to 1.53), polystyrenes (refractive index:1.59 to 1.60), aliphatic polycarbonates (refractive index: 1.48 to1.55), aromatic polycarbonates (refractive index: 1.58 to 1.59), ASresins (refractive index: 1.52 to 1.58), MS resins (refractive index:1.56 to 1.59), and rigid polyvinyl chlorides (refractive index: 1.52 to1.54).

The refractive index of the thermoplastic resin (D) can be measured bythe method described in the section of EXAMPLES below.

<Amounts of Graft Copolymer (C) and Thermoplastic Resin (D)>

In the thermoplastic resin composition of the first invention, theamounts of the graft copolymer (C) and the thermoplastic resin (D) arenot particularly limited. In general, the amount of the graft copolymer(C) is 5 to 70 parts by mass, preferably 10 to 50 parts by mass, and theamount of the thermoplastic resin (D) is 30 to 95 parts by mass,preferably 50 to 90 parts by mass, the amounts being relative to 100parts by mass of the total of the graft copolymer (C) and thethermoplastic resin (D). When the amount of the graft copolymer (C) isless than the above range and the amount of the thermoplastic resin (D)is over the above range, the impact resistance of the resultingthermoplastic resin composition is not sufficient. When the amount ofthe graft copolymer (C) is over the above range and the amount of thethermoplastic resin (D) is less than the above range, the resultingthermoplastic resin composition tends not to be provided with, forexample, intrinsic functions of the thermoplastic resin (D), such ashardness of acrylic resins and heat resistance of aromaticpolycarbonates.

<Additives>

In addition to the graft copolymer (C) and the thermoplastic resin (D),other commonly used additives such as lubricants, pigments, dyes,fillers (e.g., carbon black, silica, and titanium oxide), heatstabilizers, oxidation degradation inhibitors, weathering agents,release agents, plasticizers, and antistatic agents can be blended withthe thermoplastic resin composition of the first invention during theproduction (mixing) or molding of the thermoplastic resin composition tothe extent that the physical properties of the thermoplastic resincomposition are not impaired.

<Method for Producing Thermoplastic Resin Composition>

The thermoplastic resin composition of the first invention can beproduced using the graft copolymer (C), the thermoplastic resin (D), andoptionally added various additives by a known method using a knownapparatus. For example, commonly used methods include a melt mixingmethod.

Examples of apparatuses used in the melt mixing method includeextruders, Banbury mixers, rollers, and kneaders. Either batch mixing orcontinuous mixing may be employed. The order of mixing of components isalso not particularly limited as long as all the components areuniformly mixed.

[Molded Article]

A molded article of the first invention is obtained by molding thethermoplastic resin composition of the first invention and is excellentin weather resistance and color developability as well as in impactresistance.

Examples of the method for molding the thermoplastic resin compositionof the first invention include injection molding, injection compressionmolding, extrusion, blow molding, vacuum molding, air-pressure forming,calender molding, and inflation molding. Of these, injection molding andinjection compression molding are preferred because these methods canachieve high mass productivity and provide molded articles with highdimensional accuracy.

Embodiment of Second Invention

Hereinafter, “abrasion resistance” means resistance to damage (abrasion,wear) that can occur when a surface of a molded article is rubbed with asoft material such as cotton work gloves, gauze, or a cloth.

“Residue” refers to a structural portion that is derived from a compoundused to produce a polymer (crosslinked particles (A-I) in the secondinvention) and incorporated into the polymer. For example, a residue Xdescribed below corresponds to the rest of a polyalkylene glycol, apolyester diol, a polycarbonate diol, or a polymer of one or morethereof from each of the two hydroxyl groups of which one hydrogen atomis removed.

In the second invention, number average molecular weights (Mn) of thecrosslinked particles (A-I) and diols incorporated as divalent residuesX are values measured using gel permeation chromatography (GPC) relativeto polystyrene standards.

The same applies to the third invention described below.

[Crosslinked Particles (A-I)]

The crosslinked particles (A-I) of the second invention are obtained bypolymerizing a monomer mixture (i-I) containing a di(meth)acrylic acidester (a) represented by the following formula (1) and having a numberaverage molecular weight (Mn) of 800 to 9,000. Therefore, thecrosslinked particles (A-I) are constituted by a structural unit derivedfrom the di(meth)acrylic acid ester (a) and a structural unit derivedfrom a monomer that is contained in the monomer mixture (i-I) describedbelow and is other than the di(meth)acrylic acid ester (a). Thestructural unit derived from the di(meth)acrylic acid ester (a) includedin the crosslinked particles (A-I) effectively serves to improve theimpact resistance and abrasion resistance of a thermoplastic resincomposition of the second invention described below.

In the above formula (1), X represents a divalent residue constituted byat least one diol selected from polyalkylene glycols, polyester diols,and polycarbonate diols. R^(1a) and R^(1b) each independently representH or CH₃.

X in the formula (1) is also referred to as a “diol residue X”. A diolcompound that is used as a material for producing the di(meth)acrylicacid ester (a) and constitutes the diol residue X in the di(meth)acrylicacid ester (a) is also referred to as an “X source”. The same applies tothe third invention described below.

<Di(Meth)Acrylic Acid Ester (a)>

The number average molecular weight (Mn) of the di(meth)acrylic acidester (a) used to produce the crosslinked particles (A-I) of the secondinvention is 800 to 9,000, preferably 1,300 to 7,000, more preferably1,800 to 5,000. When the number average molecular weight (Mn) of thedi(meth)acrylic acid ester (a) is less than 800, the impact resistanceand abrasion resistance of a thermoplastic resin composition includingthe crosslinked particles (A-I) of the second invention obtained usingthe di(meth)acrylic acid ester (a) are poor, and when the number averagemolecular weight (Mn) is more than 9,000, the flowability and colordevelopability are poor.

The structure of the diol residue X included in the di(meth)acrylic acidester (a) may be a repetition of a single structural unit or arepetition of two or more structural units. When the structure of X is arepetition of two or more structural units, the way the structural unitsalign may be such that the structural units are present randomly, thatthe structural units are present as blocks, or that the structural unitsare present alternately.

From the viewpoint of abrasion resistance, the diol residue X ispreferably a residue made of a repetition of polytetramethylene glycol(polybutylene glycol).

To constitute the di(meth)acrylic acid ester (a) satisfying the abovenumber average molecular weight (Mn), the number average molecularweight (Mn) of the X source is preferably in the range of valuesobtained by subtracting the number average molecular weight of two(meth)acrylic acid residues from the number average molecular weight(Mn) of the di(meth)acrylic acid ester (a). The number average molecularweight (Mn) of the X source is specifically 660 to 8890, preferably 1160to 6890, particularly preferably 1660 to 4890.

The method for synthesizing the X source is not particularly limited,and, typically, the X source is produced by condensation polymerizationof the above-described diol or ring-opening polymerization of cyclicethers using an acid catalyst.

Examples of the di(meth)acrylic acid ester (a) include polyethyleneglycol di(meth)acrylates including 12 or more repeating units, such asdodecaethylene glycol di(meth)acrylate, tridecaethylene glycoldi(meth)acrylate, tetradecaethylene glycol di(meth)acrylate,pentadecaethylene glycol di(meth)acrylate, and hexadecaethylene glycoldi(meth)acrylate; polypropylene glycol di(meth)acrylates including 9 ormore repeating units, such as nonapropylene glycol di(meth)acrylate,decapropylene glycol di(meth)acrylate, undecapropylene glycoldi(meth)acrylate, dodecapropylene glycol di(meth)acrylate, andtridecapropylene glycol di(meth)acrylate; and polybutylene glycoldi(meth)acrylates, i.e., polytetramethylene glycol di(meth)acrylatesincluding 7 or more repeating units, such as heptabutylene glycoldi(meth)acrylate, octabutylene glycol di(meth)acrylate, nonabutyleneglycol di(meth)acrylate, decabutylene glycol di(meth)acrylate, andundecabutylene glycol di(meth)acrylate. These can be used alone or in acombination of two or more.

The method for producing the di(meth)acrylic acid ester (a) is notparticularly limited. For example, a method (dehydration reaction) inwhich an X source is reacted with (meth)acrylic acid in the presence ofan acid catalyst to form a (meth)acrylic acid ester precursor, and thenwater formed as a by-product is removed from the system or a method(transesterification reaction) in which an X source is reacted with alower (meth)acrylic acid ester to form a (meth)acrylic acid esterprecursor, and then a lower alcohol formed as a by-product is removedcan be used.

<Monomer Mixture (i-I)>

The crosslinked particles (A-I) of the second invention are obtained bypolymerizing the monomer mixture (i-I) containing the di(meth)acrylicacid ester (a). The crosslinked particles (A-I) of the second inventionare typically obtained by copolymerizing the monomer mixture (i-I)containing the di(meth)acrylic acid ester (a) and another monomer.

The content of the di(meth)acrylic acid ester (a) in the monomer mixture(i-I) is preferably 0.1% to 90% by mass, more preferably 2% to 70% bymass, still more preferably 10% to 50% by mass. When the content of thedi(meth)acrylic acid ester (a) in the monomer mixture (i-I) is in theabove range, the color developability, impact resistance, and abrasionresistance of a thermoplastic resin composition including the resultingcrosslinked particles (A-I) can be excellent.

Examples of the monomer that is contained in the monomer mixture (i-I)and copolymerizes with the di(meth)acrylic acid ester (a) include anaromatic vinyl (b), a vinyl cyanide (c), and other monomerscopolymerizable therewith.

Examples of the aromatic vinyl (b) include styrene, α-methylstyrene, o-,m-, or p-methylstyrene, vinyl xylene, p-t-butylstyrene, andethylstyrene. These can be used alone or in a combination of two ormore. In particular, it is preferable to use at least one of styrene andα-methylstyrene.

For the content of the aromatic vinyl (b) in the monomer mixture (i-I),the proportion of the aromatic vinyl (b) is preferably 60% to 90% bymass, more preferably 65% to 80% by mass, in 100% by mass of the totalof the aromatic vinyl (b) and the vinyl cyanide (c). When the proportionof the aromatic vinyl (b) is in the above range, the flowability, colordevelopability, and impact resistance of a thermoplastic resincomposition including the resulting crosslinked particles (A-I) can beexcellent.

Examples of the vinyl cyanide (c) include acrylonitrile andmethacrylonitrile. One or more of these can be used.

For the content of the vinyl cyanide (c) in the monomer mixture (i-I),the proportion of the vinyl cyanide (c) is preferably 10% to 40% bymass, more preferably 20% to 35% by mass, in 100% by mass of the totalof the aromatic vinyl (b) and the vinyl cyanide (c). When the proportionof the vinyl cyanide (c) is in the above range, the impact resistance ofa thermoplastic resin composition including the resulting crosslinkedparticles (A-I) can be excellent.

Examples of other monomers copolymerizable with the aromatic vinyl (b)and the vinyl cyanide (c) include methacrylic acid esters such as methylmethacrylate, ethyl methacrylate, n-propyl methacrylate, 1-propylmethacrylate, n-butyl methacrylate, i-butyl methacrylate, t-butylmethacrylate, amyl methacrylate, isoamyl methacrylate, octylmethacrylate, 2-ethylhexyl methacrylate, decyl methacrylate, laurylmethacrylate, cyclohexyl methacrylate, benzyl methacrylate, and phenylmethacrylate; acrylic acid esters such as methyl acrylate, ethylacrylate, propyl acrylate, and butyl acrylate; maleimide compounds suchas N-cycloalkylmaleimides including N-methylmaleimide, N-ethylmaleimide,N-n-propylmaleimide, N-i-propylmaleimide, N-n-butylmaleimide,N-i-butylmaleimide, N-t-butylmaleimide, and N-cyclohexylmaleimide,N-arylmaleimides including N-phenylmaleimide, N-alkyl-substitutedphenylmaleimide, and N-chlorophenylmaleimide, and N-aralkylmaleimides;alkylene glycol dimethacrylates such as ethylene glycol dimethacrylate,1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate,and propylene glycol dimethacrylate; and polyvinylbenzenes such asdivinylbenzene and trivinylbenzene. These can be used alone or in acombination of two or more.

<Method for Producing Crosslinked Particles (A-I)>

The method for producing the crosslinked particles (A-I) is notparticularly limited. The crosslinked particles (A-I) are produced fromthe above-described monomer mixture (i-I) containing the di(meth)acrylicacid ester (a) by a known method such as bulk polymerization, solutionpolymerization, bulk-suspension polymerization, suspensionpolymerization, or emulsion polymerization. From the viewpoint ofstability during production and particle size control, the crosslinkedparticles (A-I) are preferably produced by what is called miniemulsionpolymerization in which part or all of the monomer mixture (i-I) issheared in water solvent in the presence of an emulsifier, preferably inthe presence of an emulsifier and a hydrophobic stabilizer, to form aminiemulsion and then copolymerized in the presence of a radicalinitiator. The radical initiator may be added before or after theminiemulsion is formed.

The radical initiator, the monomer mixture (i-I), and the emulsifier maybe added in one portion, in multiple portions, or in a continuousmanner.

From the viewpoint of workability, stability, production efficiency,etc., the amount of water solvent used in the miniemulsification ispreferably about 100 to 500 parts by mass relative to 100 parts by massof the monomer mixture (i-I) so that the solids concentration of thereaction system after the polymerization will be about 5% to 50% bymass.

As a method for applying shear in forming the miniemulsion, any knownmethod can be used. The shear may be applied in one portion, in multipleportions, in a continuous manner, or in a circular manner, and, ingeneral, the miniemulsion can be formed by using a high shear devicethat forms droplets having diameters of about 0.05 to 3.0 μm.

Examples of usable high shear devices that form miniemulsions include,but are not limited to, those exemplified, in the section of thedescription of the first invention, as those used to produce thecomposite rubber-like polymer (A).

By performing radical copolymerization after forming the miniemulsion,the stability during production is improved; for example, thedi(meth)acrylic acid ester (a), which is a high-molecular-weightproduct, is efficiently taken into a micelle, and agglomerates after thepolymerization are reduced.

Examples of emulsifiers include those exemplified, in the section of thedescription of the first invention, as those used to produce thecomposite rubber-like polymer (A). The emulsifiers may be used alone orin a combination of two or more.

The addition amount of emulsifier is typically 10 parts by mass or less,preferably, for example, 0.01 to 10 parts by mass, relative to 100 partsby mass of the monomer mixture (i-I).

When the miniemulsion is formed, adding a hydrophobic stabilizer tendsto further improve the production stability of the miniemulsion.Examples of hydrophobic stabilizers include those exemplified, in thesection of the description of the first invention, as those used toproduce the composite rubber-like polymer (A). The hydrophobicstabilizers may be used alone or as a mixture of two or more.

When a hydrophobic stabilizer is used, the amount thereof is preferably0.05 to 5 parts by mass relative to 100 parts by mass of the monomermixture (i-I). When the addition amount of hydrophobic stabilizer is notless than the above lower limit, the production stability of thecrosslinked particles (A-I) can be further improved, and when theaddition amount of hydrophobic stabilizer is not more than the aboveupper limit, there is a tendency that the color developability andimpact resistance of a thermoplastic resin composition obtained byincorporating the crosslinked particles (A-I) of the second inventioncan be good.

Examples of the radical initiator used in the polymerization stepsubsequent to the miniemulsification step include those exemplified, inthe section of the description of the first invention, as those used toproduce the composite rubber-like polymer (A). The radical initiatorsmay be used alone or in a combination of two or more.

The addition amount of radical initiator is preferably 5 parts by massor less, more preferably 3 parts by mass or less, for example, 0.001 to3 parts by mass, relative to 100 parts by mass of the monomer mixture(i-I). As described above, the radical initiator may be added before orafter the miniemulsion is formed and may be added in one portion, inmultiple portions, or in a continuous manner.

In the production of the crosslinked particles (A-I), a chain transferagent may optionally be added. Examples of chain transfer agents includethose exemplified, in the section of the description of the firstinvention, as those used to produce the composite rubber-like polymer(A). The chain transfer agents may be used alone or in a combination oftwo or more. Of these, mercaptans are preferred in terms of ease ofcontrol of molecular weight.

When a chain transfer agent is used, it may be added in one portion, inmultiple portions, or in a continuous manner. The addition amount ofchain transfer agent is typically 2.0 parts by mass or less, preferably,for example, 0.01 to 2.0 parts by mass, relative to 100 parts by mass ofthe monomer mixture (i-I).

The polymerization step subsequent to the miniemulsification step istypically performed at 40° C. to 95° C. for about 0.5 to 8 hoursfollowing the miniemulsification step.

The particle size (average particle size) of the crosslinked particles(A-I) of the second invention produced through the miniemulsificationstep and the subsequent polymerization step is preferably 0.07 to 5.0μm, more preferably 0.09 to 3.0 μm, still more preferably 0.1 to 1 μm.When the particle size of the crosslinked particles (A-I) is in theabove range, the impact resistance and abrasion resistance of athermoplastic resin composition including the resulting crosslinkedparticles (A-I) can be excellent.

The particle size of the crosslinked particles (A-I) may be controlledby any method, for example, by adjusting the type or amount ofemulsifier used and the shear force during the production of theminiemulsion.

Specifically, the average particle size of the crosslinked particles(A-I) is measured by the method described in the section of EXAMPLESbelow.

[Graft Crosslinked Particles (B-I)]

Graft crosslinked particles (B-I) of the second invention is obtained bygraft-polymerizing a monomer onto the crosslinked particles (A-I) of thesecond invention.

Examples of the monomer graft-polymerized onto the crosslinked particles(A-I) of the second invention include one or two or more selected fromaromatic vinyls, vinyl cyanides, (meth)acrylic acid esters, maleimides,and maleic anhydride. When the crosslinked particles (A-I) aregraft-polymerized, the crosslinked particles (A-I) advantageously havebetter dispersibility in a thermoplastic resin (D-I) described below toprovide a thermoplastic resin composition that is more excellent inflowability and impact resistance.

Examples of monomers such as aromatic vinyls and vinyl cyanides, amongthe monomers graft-polymerized onto the crosslinked particles (A-I),include those exemplified as monomers used in the monomer mixture (i-I)for producing the crosslinked particles (A-I) of the second invention.In particular, to provide a thermoplastic resin composition excellent inflowability and impact resistance, it is preferable to use an aromaticvinyl such as styrene and a vinyl cyanide such as acrylonitrile incombination. In this case, it is preferable to use the aromatic vinyl inan amount of 60% to 99% by mass and the vinyl cyanide in an amount of 1%to 40% by mass (provided that the total amount of the aromatic vinyl andthe vinyl cyanide is 100% by mass).

The proportions of the crosslinked particles (A-I) and the monomer usedin graft polymerization are not particularly limited, but, in general,the proportion of the crosslinked particles (A-I) is 40% to 90% by mass,and the proportion of the monomer is 10% to 60% by mass (provided thatthe total amount of the crosslinked particles (A-I) and the monomer is100% by mass). When the proportions of the crosslinked particles (A-I)and the monomer are in the above ranges, the dispersibility in thethermoplastic resin (D-I) described below is good, and a thermoplasticresin composition having improved flowability and impact resistance isprovided.

For good dispersibility in the thermoplastic resin (D-I) describedbelow, the graft crosslinked particles (B-I) preferably have a graftrate of 23% to 100%.

The graft rate G of the graft crosslinked particles (B-I) is determinedby the following formula (4).

G=100(P−E)/E  (4)

P: mass of acetone insoluble fraction (mass (g) of acetone insolublefraction after being vacuum-dried, the acetone insoluble fraction beingobtained by washing of graft crosslinked particles (B-I) with methanol,extraction with acetone, and centrifugal separation into acetone solublefraction and acetone insoluble fraction)

E: mass (g) of graft crosslinked particles (B-I) before graftpolymerization

The method for producing the graft crosslinked particles (B-I) is notparticularly limited. The graft crosslinked particles (B-I) are producedby a known method such as bulk polymerization, solution polymerization,bulk-suspension polymerization, suspension polymerization, or emulsionpolymerization. When the crosslinked particles (A-I) are prepared byminiemulsion polymerization and provided in the form of emulsifiedlatex, the graft polymerization may also be carried out by emulsionpolymerization. Examples of emulsion graft polymerization include amethod in which the monomer is added in one portion, in a continuousmanner, or in an intermittent manner in the presence of an emulsion ofthe crosslinked particles (A-I) to cause radical polymerization. In thegraft polymerization, a chain transfer agent for molecular weightadjustment and graft rate control, a known inorganic electrolyte foradjusting the viscosity and pH of latex, etc. can be used. The type andaddition amount of these are not particularly limited. In the emulsiongraft polymerization, various emulsifiers can be used as required. As achain transfer agent, emulsifier, and radical initiator, for example,those exemplified as those used in the production of the crosslinkedparticles (A-I) can be used.

The method for obtaining the graft crosslinked particles (B-I) in theform of granules from the emulsion of the graft crosslinked particles(B-I) produced as described above is not particularly limited. Examplesinclude a method in which the emulsion is put in hot water containing adissolved coagulant and allowed to coagulate and solidify and a spraydrying method. Examples of usable coagulants include inorganic acidssuch as sulfuric acid, hydrochloric acid, phosphoric acid, and nitricacid and metal salts such as calcium chloride, calcium acetate, andaluminum sulfate.

[Thermoplastic Resin Composition]

The thermoplastic resin composition of the second invention includes thecrosslinked particles (A-I) and/or the graft crosslinked particles (B-I)of the second invention described above and the thermoplastic resin(D-I).

<Thermoplastic Resin (D-I)>

Examples of the thermoplastic resin (D-I) in the second inventioninclude styrene resins such as AS (acrylonitrile-styrene) resinscontaining the above-described aromatic vinyl (b) and the vinyl cyanide(c) as principal components, styrene-acrylonitrile-phenylmaleimidecopolymer resins, ABS resins, AES resins, and AAS resins; polyolefinresins such as polystyrene, poly(meth)acrylate resins, polyethylene, andpolypropylene; and polycarbonate (PC), polyphenylene ether, modifiedpolyphenylene ether, polybutylene terephthalate, polyethyleneterephthalate, polyamide, polyester, polysulfone, polyetherketone,polyethersulfone, fluorocarbon resins, silicone resins, polyesterelastomers, and polycaprolactone. One of these resins may be used alone,or two or more of them may be used in combination.

<Proportions of Crosslinked Particles (A-I)/Graft Crosslinked Particles(B-I)>

The content of the crosslinked particles (A-I) and/or the graftcrosslinked particles (B-I) in the thermoplastic resin composition ofthe second invention is preferably 1% to 95% by mass, more preferably 5%to 80% by mass, particularly preferably 10% to 50% by mass, providedthat the total amount of the crosslinked particles (A-I) and/or thegraft crosslinked particles (B-I) and the thermoplastic resin (D-I) is100% by mass. When the content of the crosslinked particles (A-I) and/orthe graft crosslinked particles (B-I) is in the above range, the colordevelopability, impact resistance, and abrasion resistance of thethermoplastic resin composition are more excellent.

<Additives>

In addition to the crosslinked particles (A-I) and/or the graftcrosslinked particles (B-I) and the thermoplastic resin (D-I), othercommonly used additives such as lubricants, colorants including pigmentsand dyes, fillers (e.g., carbon black, silica, and titanium oxide),processing aids, heat stabilizers, antioxidants, weathering agents,release agents, plasticizers, and antistatic agents can be blended withthe thermoplastic resin composition of the second invention during theproduction (mixing) or molding of the thermoplastic resin composition tothe extent that the physical properties of the thermoplastic resincomposition are not impaired.

<Method for Producing Thermoplastic Resin Composition>

The thermoplastic resin composition of the second invention can beproduced using the crosslinked particles (A-I) and/or the graftcrosslinked particles (B-I), the thermoplastic resin (D-I), andoptionally added various additives by a known method using a knownapparatus. For example, commonly used methods include a melt mixingmethod. Examples of apparatuses used in the melt mixing method includeextruders, Banbury mixers, rollers, and kneaders. Either batch mixing orcontinuous mixing may be employed. The order of mixing of components isalso not particularly limited as long as all the components areuniformly mixed.

[Molded Article]

A molded article of the second invention is obtained by molding thethermoplastic resin composition of the second invention. The moldedarticle is excellent in color developability, flowability, impactresistance, and abrasion resistance and is excellent in dimensionalstability and shape accuracy due to its small mold shrinkage rate.

Examples of the method for molding the thermoplastic resin compositionof the second invention include injection molding, injection compressionmolding, extrusion, blow molding, vacuum molding, air-pressure forming,calender molding, and inflation molding. Of these, injection molding andinjection compression molding are preferred because these methods canachieve high mass productivity and provide molded articles with highdimensional accuracy.

The molded article of the second invention obtained by molding thethermoplastic resin composition of the second invention is excellent incolor developability, flowability, impact resistance, and abrasionresistance and is excellent in dimensional stability and shape accuracydue to its small mold shrinkage rate, and thus is suitable forautomotive interior and exterior parts, office machines, householdelectrical appliances, building materials, etc.

Embodiment of Third Invention

In the third invention, “abrasion resistance” and “residue” each havethe same meaning as in the second invention. Number average molecularweights (Mn) of crosslinked particles (A-II) and diols incorporated asdivalent residues X are values measured using gel permeationchromatography (GPC) relative to polystyrene standards.

[Crosslinked Particles (A-II)]

The crosslinked particles (A-II) of the third invention are obtained bypolymerizing a monomer mixture (i-II) containing a di(meth)acrylic acidester (a) represented by the following formula (1) and having a numberaverage molecular weight of 800 to 9,000 and a mono(meth)acrylic acidester (d). The content of the di(meth)acrylic acid ester (a) in 100% bymass of the monomer mixture (i-II) is 20% to 80% by mass. Therefore, thecrosslinked particles (A-II) of the third invention are constituted by astructural unit derived from the di(meth)acrylic acid ester (a), astructural unit derived from the mono(meth)acrylic acid component (d),and a structural unit derived from an additional vinyl compound (e)described below that is optionally used and are characterized by havinga volume average particle size of 0.07 to 2.0 μm. The structural unitderived from the di(meth)acrylic acid ester (a) constituting thecrosslinked particles (A-II) effectively serves to improve the impactresistance and abrasion resistance of a thermoplastic resin compositionof the third invention described below.

In the above formula (1), X represents a divalent residue constituted byat least one diol selected from polyalkylene glycols, polyester diols,and polycarbonate diols. R^(1a) and R^(1b) each independently representH or CH₃.

The monomer mixture (i-II), which is a raw material of the crosslinkedparticles (A-II) of the third invention, contains the di(meth)acrylicacid ester (a) and the mono(meth)acrylic acid component (d) as essentialcomponents and contains the additional vinyl compound (e) that isoptionally used.

Hereinafter, X in the formula (1) is also referred to as a “diol residueX”. A diol compound that is used as a material for producing thedi(meth)acrylic acid ester (a) and constitutes the diol residue X in thedi(meth)acrylic acid ester (a) is also referred to as an “X source”.

<Di(Meth)Acrylic Acid Ester (a)>

The di(meth)acrylic acid ester (a) used to produce the crosslinkedparticles (A-II) of the third invention is the same as thedi(meth)acrylic acid ester (a) used to produce the crosslinked particles(A-I) of the second invention. The number average molecular weight (Mn),the diol residue X included in the di(meth)acrylic acid ester (a), thenumber average molecular weight (Mn) of an X source, the method forsynthesizing the X source, examples of the di(meth)acrylic acid ester(a), and the production method thereof are the same as in the secondinvention.

The content of the di(meth)acrylic acid ester (a) in the monomer mixture(i-II) (i.e., the total of the di(meth)acrylic acid ester (a), themono(meth)acrylic acid component (d), and the additional vinyl compound(e) described below that is optionally used) is 20% to 80% by mass, morepreferably 25% to 70% by mass, still more preferably 30% to 50% by mass.When the content of the di(meth)acrylic acid ester (a) in the monomermixture (i-II) is less than 20% by mass, the impact resistance andabrasion resistance of a thermoplastic resin composition including theresulting crosslinked particles (A-II) are poor, and when the content ismore than 90% by mass, the color developability is poor.

<Mono(Meth)Acrylic Acid Component (d)>

The mono(meth)acrylic acid component (d) is a (meth)acrylic acid and/ora mono(meth)acrylic acid ester.

Examples include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl(meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate,cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, stearyl(meth)acrylate, lauryl (meth)acrylate, isobornyl (meth)acrylate, benzyl(meth)acrylate, phenyl (meth)acrylate, glycidyl (meth)acrylate,hydroxyethyl (meth)acrylate, and (meth)acrylic acid. Of these,(meth)acrylic acid monoalkyl esters having alkyl groups of 1 to 8 carbonatoms are preferred. These may be used alone or in a combination of twoor more.

The content of the mono(meth)acrylic acid component (d) in the monomermixture (i-II) is preferably 1% to 80% by mass, more preferably 25% to75% by mass, still more preferably 50% to 70% by mass. When the contentof the mono(meth)acrylic acid component (d) is in the above range, amolded article having an excellent balance of color developability,weather resistance, impact resistance, and abrasion resistance can beobtained from a thermoplastic resin composition including the resultingcrosslinked particles (A-II).

<Additional Vinyl Compound (e)>

The additional vinyl compound (e) that is optionally used is notparticularly limited as long as it is copolymerizable with thedi(meth)acrylic acid ester (a) and the mono(meth)acrylic acid component(d). Examples include aromatic vinyls such as styrene, α-methylstyrene,o-, m-, or p-methylstyrene, vinyl xylene, p-t-butylstyrene, and ethylstyrene; vinyl cyanides such as acrylonitrile and methacrylonitrile;maleimides such as N-cyclohexylmaleimide and N-phenylmaleimide; maleicanhydride; alkylene glycol dimethacrylates such as ethylene glycoldimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycoldimethacrylate, and propylene glycol dimethacrylate; andpolyvinylbenzenes such as divinylbenzene and trivinylbenzene. These maybe used alone or as a mixture of two or more.

Of these, styrene is preferably used to achieve a refractive indexcloser to that of a thermoplastic resin (D-II).

The content of the additional vinyl compound (e) in the monomer mixture(i-II) is 0% to 70% by mass. When the proportion of the additional vinylcompound (e) is in the above range, the flowability a thermoplasticresin composition including the resulting crosslinked particles (A-II)is excellent, and a molded article having excellent color developabilitycan be obtained.

When styrene is used as the additional vinyl compound (e), the contentof styrene in the monomer mixture (i-II) is preferably 3% to 30% bymass, particularly preferably 5% to 20% by mass, to achieve a refractiveindex closer to that of the thermoplastic resin (D-II).

<Method for Producing Crosslinked Particles (A-II)>

The method for producing the crosslinked particles (A-II) is notparticularly limited. The crosslinked particles (A-II) are produced fromthe above-described monomer mixture (i-II) containing thedi(meth)acrylic acid ester (a), the mono(meth)acrylic acid component(d), and the additional vinyl compound (e) that is optionally used by aknown method such as bulk polymerization, solution polymerization,bulk-suspension polymerization, suspension polymerization, or emulsionpolymerization. From the viewpoint of stability during production andparticle size control, the crosslinked particles (A-I) are preferablyproduced by what is called miniemulsion polymerization in which part orall of the monomer mixture (i-II) is sheared in water solvent in thepresence of an emulsifier, preferably in the presence of an emulsifierand a hydrophobic stabilizer, to form a miniemulsion and thencopolymerized in the presence of a radical initiator. The radicalinitiator may be added before or after the miniemulsion is formed, andthe radical initiator, the monomer mixture (i-II) (i.e., thedi(meth)acrylic acid ester (a), the mono(meth)acrylic acid component(d), and the additional vinyl compound (e)), and the emulsifier may beadded in one portion, in multiple portions, or in a continuous manner.

From the viewpoint of workability, stability, production efficiency,etc., the amount of water solvent used in the miniemulsification ispreferably about 100 to 500 parts by mass relative to 100 parts by massof the monomer mixture (i-II) so that the solids concentration of thereaction system after the polymerization will be about 5% to 50% bymass.

As a method for applying shear in forming the miniemulsion, any knownmethod can be used. The shear may be applied in one portion, in multipleportions, in a continuous manner, or in a circular manner, and, ingeneral, the miniemulsion can be formed by using a high shear devicethat forms droplets having diameters of about 0.05 to 3.0 μm. Examplesof usable high shear devices that form miniemulsions include, but arenot limited to, those exemplified, in the section of the description ofthe first invention, as those used to produce the composite rubber-likepolymer (A).

By performing radical copolymerization after forming the miniemulsion,the stability during production is improved; for example, thedi(meth)acrylic acid ester (a), which is a high-molecular-weightproduct, is efficiently taken into a micelle, and agglomerates after thepolymerization are reduced.

Examples of emulsifiers include those exemplified, in the section of thedescription of the first invention, as those used to produce thecomposite rubber-like polymer (A). These emulsifiers may be used aloneor in a combination of two or more.

The addition amount of emulsifier is typically 10 parts by mass or less,preferably, for example, 0.01 to 10 parts by mass, relative to 100 partsby mass of the monomer mixture (i-II).

When the miniemulsion is formed, adding a hydrophobic stabilizer tendsto further improve the production stability of the miniemulsion.Examples of hydrophobic stabilizers include those exemplified, in thesection of the description of the first invention, as those used toproduce the composite rubber-like polymer (A). The hydrophobicstabilizers may be used alone or as a mixture of two or more.

When a hydrophobic stabilizer is used, the amount thereof is preferably0.05 to 5 parts by mass relative to 100 parts by mass of the monomermixture (i-II). When the addition amount of hydrophobic stabilizer isnot less than the above lower limit, the production stability of thecrosslinked particles (A-II) can be further improved, and when theaddition amount of hydrophobic stabilizer is not more than the aboveupper limit, there is a tendency that the color developability andimpact resistance of a thermoplastic resin composition obtained byincorporating the crosslinked particles (A-II) of the third inventioncan be good.

Examples of the radical initiator used in the polymerization stepsubsequent to the miniemulsification step include those exemplified, inthe section of the description of the first invention, as those used toproduce the composite rubber-like polymer (A). The radical initiatorsmay be used alone or in a combination of two or more.

The addition amount of radical initiator is preferably 5 parts by massor less, more preferably 3 parts by mass or less, for example, 0.001 to3 parts by mass, relative to 100 parts by mass of the monomer mixture(i-II). As described above, the radical initiator may be added before orafter the miniemulsion is formed and may be added in one portion, inmultiple portions, or in a continuous manner.

In the production of the crosslinked particles (A-II), a chain transferagent may optionally be added. Examples of chain transfer agents includethose exemplified, in the section of the description of the firstinvention, as those used to produce the composite rubber-like polymer(A). The chain transfer agents may be used alone or in a combination oftwo or more. Of these, mercaptans are preferred in terms of ease ofcontrol of molecular weight.

When a chain transfer agent is used, it may be added in one portion, inmultiple portions, or in a continuous manner, and the addition amountthereof is typically 2.0 parts by mass or less, preferably, for example,0.01 to 2.0 parts by mass, relative to 100 parts by mass of the monomermixture (i-II).

The polymerization step subsequent to the miniemulsification step istypically performed at 40° C. to 95° C. for about 0.5 to 8 hoursfollowing the miniemulsification step.

<Particle Size>

The particle size (average particle size) of the crosslinked particles(A-II) of the third invention is 0.07 to 2.0 μm, preferably 0.09 to 1.0μm, still more preferably 0.1 to 0.5 μm. When the average particle sizeof the crosslinked particles (A-II) in less than 0.07 μm, the impactresistance of a thermoplastic resin composition including the resultingcrosslinked particles (A-II) is poor, and when the average particle sizeis more than 2.0 μm, the color developability and abrasion resistance ofa thermoplastic resin composition including the resulting crosslinkedparticles (A-II) are poor.

Specifically, the average particle size of the crosslinked particles(A-II) is measured by the method described in the section of EXAMPLESbelow.

[Graft Crosslinked Particles (B-II)]

Graft crosslinked particles (B-II) of the third invention are obtainedby graft-polymerizing a monomer onto the crosslinked particles (A-II) ofthe third invention.

Examples of the monomer graft-polymerized onto the crosslinked particles(A-II) of the third invention include one or two or more selected fromaromatic vinyls, vinyl cyanides, (meth)acrylic acid esters, maleimides,and maleic anhydride. When the crosslinked particles (A-II) aregraft-polymerized, the crosslinked particles (A-II) advantageously havebetter dispersibility in the thermoplastic resin (D-II) described belowto provide a thermoplastic resin molded article that is more excellentin color developability and impact resistance.

Examples of the monomer graft-polymerized onto the crosslinked particles(A-II) include the mono(meth)acrylic acid components (d) exemplified inthe section of the crosslinked particles (A-II) of the third inventionand (meth)acrylic acid esters, aromatic vinyls, vinyl cyanides,maleimides, and maleic anhydride exemplified in the additional vinylcompound (e), and one or more of these can be used. Of these,(meth)acrylic acid esters are suitable for use in order to provide athermoplastic resin molded article excellent in color developability andweather resistance. In particular, it is preferable to use methylmethacrylate and methyl acrylate in combination such that the amount ofmethyl methacrylate is 90% to 99.9% by mass and the amount of methylacrylate is 0.1% to 10% by mass, relative to 100% by mass of their totalamount.

The proportions of the crosslinked particles (A-II) and the monomer usedin graft polymerization are not particularly limited, but, in general,the proportion of the crosslinked particles (A-II) is 40% to 90% bymass, and the proportion of the monomer is 10% to 60% by mass (providedthat the total amount of the crosslinked particles (A-II) and themonomer is 100% by mass). When the proportions of the crosslinkedparticles (A-II) and the monomer are in the above ranges, thedispersibility in the thermoplastic resin (D-II) described below isgood, and a thermoplastic resin composition having improved colordevelopability and impact resistance is provided.

For good dispersibility in the thermoplastic resin (D-II) describedbelow, the graft crosslinked particles (B-II) preferably have a graftrate of 23% to 100%.

The method for calculating the graft rate of the graft crosslinkedparticles (B-II) is the same as the method for calculating the graftrate of the graft crosslinked particles (B-I) in the second invention.

The method for producing the graft crosslinked particles (B-II) and themethod for obtaining the graft crosslinked particles (B-II) in the formof granules from an emulsion of the graft crosslinked particles (B-II)produced are the same as those for the graft crosslinked particles (B-I)of the second invention.

[Thermoplastic Resin Composition]

The thermoplastic resin composition of the third invention includes thecrosslinked particles (A-II) and/or the graft crosslinked particles(B-II) of the third invention and the thermoplastic resin (D-II).

<Thermoplastic Resin (D-II)>

Examples of the thermoplastic resin (D-II) in the third inventioninclude poly(meth)acrylate resins containing the above-describedmono(meth)acrylic acid ester (d) as a principal component; polyolefinresins such as polyethylene and polypropylene; polycarbonate (PC),polyphenylene ether, modified polyphenylene ether, polybutyleneterephthalate, polyethylene terephthalate, polyamide, polyester,polysulfone, polyetherketone, polyethersulfone, fluorocarbon resins,silicone resins, polyester elastomers, polycaprolactone, aromaticpolyester elastomers, polyamide elastomers, AS-grafted polyethylene,AS-grafted polypropylene; and styrene resins such as polystyrene, ASresins, and ABS resins. These resins may be used alone or in acombination of two or more.

<Proportions of Crosslinked Particles (A-II)/Graft Crosslinked Particles(B-II)>

The content of the crosslinked particles (A-II) and/or the graftcrosslinked particles (B-II)) in the thermoplastic resin composition ofthe third invention is preferably 1% to 90% by mass, more preferably 10%to 70% by mass, still more preferably 20% to 50% by mass, provided thatthe total amount of the crosslinked particles (A-II) and/or the graftcrosslinked particles (B-II) and the thermoplastic resin (D-II) is 100%by mass. When the content of the crosslinked particles (A-II) and/or thegraft crosslinked particles (B-II) is in the above range, athermoplastic resin composition excellent in color developability,abrasion resistance, and impact resistance is provided.

<Additives>

Similarly to the thermoplastic resin composition of the secondinvention, in addition to the crosslinked particles (A-II) and/or thegraft crosslinked particles (B-II) and the thermoplastic resin (D-II),other commonly used additives can be blended with the thermoplasticresin composition of the third invention during the production (mixing)or molding of the thermoplastic resin composition to the extent that thephysical properties of the thermoplastic resin composition are notimpaired.

<Method for Producing Thermoplastic Resin Composition>

The thermoplastic resin composition of the third invention is producedsimilarly to the thermoplastic resin composition of the second inventionby using the crosslinked particles (A-II) and/or the graft crosslinkedparticles (B-II), the thermoplastic resin (D-II), and optionally addedvarious additives.

[Molded Article]

A molded article of the third invention is obtained by molding thethermoplastic resin composition of the third invention and is excellentin flowability during molding, color developability, weather resistance,impact resistance, and abrasion resistance.

The method for molding the thermoplastic resin composition of the thirdinvention is the same as the method for molding the thermoplastic resincomposition of the second invention, and the preferred molding method isalso the same.

The molded article of the third invention obtained by molding thethermoplastic resin composition of the third invention is excellent incolor developability, weather resistance, impact resistance, andabrasion resistance and thus is suitable for automotive interior andexterior parts, office machines, household electrical appliances,building materials, etc.

Embodiment of Fourth Invention [Rubbery Polymer (A-III)]

A rubbery polymer (A-III) of the fourth invention is obtained byminiemulsion polymerization reaction of an alkyl (meth)acrylate,preferably, a mixture (i-III) containing an alkyl (meth)acrylate, ahydrophobe, and an emulsifier. The rubbery polymer (A-III) is typicallyproduced by miniemulsifying the mixture (i-III) containing an alkyl(meth)acrylate, a hydrophobe, and an emulsifier and polymerizing theresulting miniemulsion.

In the miniemulsion polymerization, monomer oil droplets of about 100 to1000 nm are prepared by applying a strong shear force by using anultrasonic oscillator or the like. In this process, emulsifier moleculesare preferentially adsorbed on the surface of the monomer oil droplets,and free emulsifiers and micelles become substantially absent in anaqueous medium. Therefore, in ideal miniemulsion-type polymerization,monomer radicals are never to be separated into an aqueous phase and anoil phase, and polymerization proceeds with monomer oil droplets servingas nuclei of particles. As a result, the monomer oil droplets formed areconverted as they are into polymer particles, making it possible toobtain polymer nanoparticles having a narrow particle size distribution.The polymer particles having a narrow particle size distribution, evenwhen having a particle size of 200 nm or more, exhibit good colordevelopability and good molded appearance.

By contrast, in the case of polymer particles having a particle size of200 nm or more prepared by standard emulsion polymerization, theirparticle size distribution is difficult to control, and the polymerparticles have a wide particle size distribution, thus resulting in poorcolor developability and poor molded appearance.

<Method for Producing Rubbery Polymer (A-III)>

The miniemulsion polymerization for producing the rubbery polymer(A-III) of the fourth invention may, but does not necessarily, include,for example, a step of mixing a monomer including an alkyl(meth)acrylate as an essential component, an emulsifier, and ahydrophobe, and, furthermore, preferably a radical polymerizationinitiator, a step of applying a shear force to the resulting mixture(i-III) to prepare a pre-emulsion, and a step of polymerizing themixture (i-III) by heating to a polymerization starting temperature. Inthe miniemulsion polymerization, the monomer for polymerization and theemulsifier are mixed, and the shearing step, for example, by ultrasonicirradiation is then performed, whereby the shear force causes themonomer to tear to form monomer oil microdroplets covered with theemulsifier. After this, the monomer oil microdroplets are polymerized asthey are by heating to the polymerization starting temperature of theradical polymerization initiator to obtain polymer fine particles.

The shear force for forming a miniemulsion can be added by any knownmethod. Examples of usable high shear devices that form miniemulsionsinclude, but are not limited to, those exemplified, in the section ofthe description of the first invention, as those used to produce thecomposite rubber-like polymer (A).

From the viewpoint of workability, stability, production efficiency,etc., the amount of water solvent used in the miniemulsification ispreferably about 100 to 500 parts by mass relative to 100 parts by massof the mixture (i-III) excluding water so that the solids concentrationof the reaction system after the polymerization will be about 5% to 50%by mass.

<<Alkyl (Meth)Acrylate>>

Examples of the alkyl (meth)acrylate constituting the rubbery polymer(A-III) include alkyl acrylates having alkyl groups of 1 to 18 carbonatoms, such as methyl acrylate, ethyl acrylate, n-propyl acrylate,n-butyl acrylate, and 2-ethylhexyl acrylate; and alkyl methacrylateshaving alkyl groups of 1 to 18 carbon atoms, such as hexyl methacrylate,2-ethylhexyl methacrylate, and n-dodecyl methacrylate.

Among the alkyl (meth)acrylates, n-butyl acrylate is preferred becausethe impact resistance and gloss of a molded article obtained from athermoplastic resin composition are improved. The alkyl (meth)acrylatesmay be used alone or in a combination of two or more.

<<Hydrophobe>>

Examples of hydrophobes include hexadecane, olive oil, polystyreneshaving mass average molecular weights (Mw) of 500 to 5000, siloxaneshaving mass average molecular weights (Mw) of 500 to 5000, cetylalcohol, stearyl alcohol, palmityl alcohol, and behenyl alcohol. Otherexamples include water-insoluble monomers, such as vinyl esters ofcarboxylic acids having 12 to 22 carbon atoms, vinyl ethers of alcoholshaving 12 to 30 carbon atoms, and alkyl acrylates having 12 to 22 carbonatoms. Specifically, examples of hydrophobic monomers include hexylacrylate, p-methylstyrene, 2-ethylhexyl acrylate, decyl acrylate,stearyl acrylate, lauryl methacrylate, and stearyl methacrylate.Examples of hydrophobic chain transfer agents include lauryl mercaptan(normal dodecyl mercaptan). Examples of hydrophobic peroxides includelauroyl peroxide. These may be used alone or in a combination of two ormore. Of these, hexadecane is preferably, but not necessarily, used as ahydrophobe.

The use of a hydrophobe suppresses the increase in ununiformity ofparticle size due to Ostwald ripening and enables the synthesis ofmonodisperse latex particles.

The addition amount of hydrophobe is preferably 0.1 to 10 parts by mass,more preferably 1 to 3 parts by mass, relative to 100 parts by mass ofthe alkyl (meth)acrylate.

<<Emulsifier>>

As an emulsifier used when the rubbery polymer is produced, knownemulsifiers, for example, carboxylic-acid-based emulsifiers, such asalkali metal salts of oleic acid, palmitin acid, stearic acid, and rosinacid and alkali metal salts of alkenyl succinic acid; and anionicemulsifiers selected from alkyl sulfuric acid esters, sodiumalkylbenzene sulfonates, sodium alkyl sulfosuccinates, polyoxyethylenenonylphenyl ether sodium sulfate, etc., can be used alone or in acombination of two or more.

The addition amount of emulsifier is preferably 0.01 to 1.0 part bymass, more preferably 0.05 to 0.5 parts by mass, relative to 100 partsby mass of the alkyl (meth)acrylate.

<<Radical Polymerization Initiator>>

Examples of the radical polymerization initiator used in thepolymerization step subsequent to the miniemulsification step includethose exemplified, in the section of the description of the firstinvention, as those used to produce the composite rubber-like polymer(A). The radical polymerization initiators may be used alone or in acombination of two or more.

The addition amount of radical polymerization initiator is typically 5parts by mass or less, preferably 3 parts by mass or less, for example,0.001 to 3 parts by mass, relative to 100 parts by mass of the alkyl(meth)acrylate.

The radical polymerization initiator may be added before or after theminiemulsion is formed and may be added in one portion, in multipleportions, or in a continuous manner.

<<Rubber Component>>

In producing the rubbery polymer (A-III), another rubber component maybe incorporated into the mixture (i-III) to produce the rubbery polymer(A-III) made of a composite rubber. In this case, examples of the otherrubber component include diene rubbers, such as polybutadiene, andpolyorganosiloxanes. By polymerizing the alkyl (meth)acrylate in thepresence of such a rubber component, the rubbery polymer (A-III) made ofdiene/alkyl (meth)acrylate composite rubber or polyorganosiloxane/alkyl(meth)acrylate composite rubber combined with alkyl (meth)acrylaterubber such as butyl acrylic rubber is obtained. The composite rubberrelated to the fourth invention is not limited thereto, and the rubbercomponents to be combined can be used alone or in a combination of twoor more.

<<Crosslinking Agent>>

In producing the rubbery polymer (A-III), the polymerization ispreferably performed with a crosslinking agent being added to themixture (i-III) in order to introduce a crosslinked structure into apolyalkyl (meth)acrylate component obtained from the alkyl(meth)acrylate described above. In the case of the crosslinked rubberypolymer (A-III) obtained using a crosslinking agent, crosslinkedportions thereof also function as graft crosslinking points for a vinylmonomer to be grafted in the production of a graft copolymer (B-III) ofthe fourth invention.

Examples of the crosslinking agent used in this case include allyl(meth)acrylate, butylene di(meth)acrylate, ethylene glycoldi(meth)acrylate, propylene glycol di(meth)acrylate, 1,3-butylene glycoldi(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, triallylcyanurate, and triallyl isocyanurate. The crosslinking agents may beused alone or in a combination of two or more.

The amount of crosslinking agent used is not particularly limited, butpreferably, the amount of crosslinking agent is 0.1 to 5.0 parts by massrelative to 100 parts by mass of the total of the crosslinking agent andthe alkyl (meth)acrylate.

<Average Particle Size and Particle Size Distribution>

The rubbery polymer (A-III) of the fourth invention obtained by theminiemulsion polymerization described above preferably satisfies (2) or(3) below, wherein an average particle size (X) is represented by X; alargest 10% frequency particle size (Y), which is a particle size atwhich the cumulative frequency from the largest value in a particle sizedistribution curve reaches 10%, is represented by Y; and a smallest 10%frequency particle size (Z), which is a particle size at which thecumulative frequency from the smallest value in the particle sizedistribution curve reaches 10%, is represented by Z.

(2) The average particle size (X) satisfies X≤300 nm, the largest 10%frequency particle size (Y) satisfies Y≤1.6X, and the smallest 10%frequency particle size (Z) satisfies Z≥0.7X.

(3) The average particle size (X) satisfies X=300 to 800 nm, the largest10% frequency particle size (Y) satisfies Y≤1.7X, and the smallest 10%frequency particle size (Z) satisfies Z≥0.6X.

When the rubbery polymer (A-III) of the fourth invention has a uniformparticle size satisfying the particle size distribution (2) or (3)above, a thermoplastic resin molded article particularly excellent inimpact resistance, molded appearance, and color developability can beobtained by incorporating the graft copolymer (B-III) produced using therubbery polymer (A-III) into a thermoplastic resin composition. Whenminiemulsion polymerization is used, the rubbery polymer (A-III)satisfying the average particle size and particle size distributiondescribed above can be readily produced.

The average particle size (X) of the rubbery polymer (A-III) of thefourth invention is more preferably 200 to 400 nm. For the particle sizedistribution of the rubbery polymer (A-III) of the fourth invention,more preferably, the largest 10% frequency particle size (Y) satisfiesY≤1.4X, and the smallest 10% frequency particle size (Z) satisfiesZ≥0.8X.

The average particle size and particle size distribution of the rubberypolymer (A-III) of the fourth invention are measured by the methodsdescribed in the section of EXAMPLES below.

[Graft Copolymer (B-III)]

The graft copolymer (B-III) of the fourth invention includes the rubberypolymer (A-III) of the fourth invention and at least one monomerselected from aromatic vinyl compounds, (meth)acrylic acid esters, andvinyl cyanide compounds (hereinafter referred to as the “graft monomercomponent”) graft-polymerized onto the rubbery polymer (A-III).

The graft monomer component may include a vinyl monomer other thanaromatic vinyl compounds, (meth)acrylic acid esters, and vinyl cyanidecompounds.

Of these graft monomer components, the use of a mixture of an aromaticvinyl compound, preferably styrene, and a vinyl cyanide compound,preferably acrylonitrile, advantageously provides the graft copolymer(B-III) with excellent thermal stability. In this case, the proportionsof the aromatic vinyl compound such as styrene and the vinyl cyanidecompound such as acrylonitrile are preferably such that the proportionof the aromatic vinyl compound is 50% to 90% by mass and the proportionof the vinyl cyanide compound is 10% to 50% by mass (provided that thetotal amount of the aromatic vinyl compound and the vinyl cyanidecompound is 100% by mass).

The graft copolymer (B-III) is preferably obtained by emulsion graftpolymerization of 10% to 90% by mass of the rubbery polymer (A-III) and90% to 10% by mass of the graft monomer component (provided that thetotal amount of the rubbery polymer (A-III) and the graft monomercomponent is 100% by mass). This is because a molded article having anexcellent appearance is provided. More preferably, the proportion of therubbery polymer (A-III) is 30% to 70% by mass, and the proportion of thegraft monomer component is 70% to 30% by mass.

Examples of the method for graft-polymerizing the graft monomercomponent onto the rubbery polymer (A-III) include a method in which thegraft monomer component is added to a latex of the rubbery polymer(A-III) obtained by miniemulsion polymerization and polymerization isperformed in a single-stage or multistage manner. When polymerization isperformed in a multistage manner, the polymerization is preferablyperformed by adding the graft monomer component in multiple portions orin a continuous manner in the presence of a rubber latex of the rubberypolymer (A-III). By such a polymerization method, good polymerizationstability is provided, and a latex having the desired particle size andparticle size distribution can be stably obtained. Examples ofpolymerization initiators used for the graft polymerization includethose which are the same as the above-described radical polymerizationinitiators used for miniemulsion polymerization of the alkyl(meth)acrylate.

When the graft monomer component is polymerized onto the rubbery polymer(A-III), an emulsifier can be added in order to stabilize the latex andcontrol the average particle size the resulting graft copolymer (B-III).Examples of emulsifiers used here include, but are not limited to, thosewhich are the same as the above-described emulsifiers used forminiemulsion polymerization of the alkyl (meth)acrylate. Preferredemulsifiers are anionic emulsifiers and nonionic emulsifiers.

The amount of emulsifier used when the graft monomer component ispolymerized is not particularly limited but is preferably 0.1 to 10parts by mass, more preferably 0.2 to 5 parts by mass, relative to 100parts by mass of the resulting graft copolymer (B-III).

Examples of the method for collecting the graft copolymer (B-III) fromthe latex of the graft copolymer (B-III) obtained by emulsionpolymerization include, but are not limited to, the following method.

The latex of the graft copolymer (B-III) is placed in hot water in whicha coagulant is dissolved to solidify the graft copolymer (B-III). Thesolidified graft copolymer (B-III) is then redispersed in water or warmwater to form a slurry, and an emulsifier residue remaining in the graftcopolymer (B-III) is eluted into water and washed. The slurry is thendehydrated with a dehydrator or the like, and the resulting solid isdried with a flash dryer or the like to thereby collect the graftcopolymer (B-III) as powder or particles.

Examples of coagulants include inorganic acids (e.g., sulfuric acid,hydrochloric acid, phosphoric acid, and nitric acid) and metal salts(e.g., calcium chloride, calcium acetate, and aluminum sulfate). Thecoagulant is appropriately selected according to the type of emulsifier.For example, when a carboxylic acid salt (e.g., a fatty acid salt orrosin acid soap) alone is used as an emulsifier, any coagulant may beused. When an emulsifier that shows stable emulsifying power even in theacidic region, such as sodium alkylbenzene sulfonate, is used as anemulsifier, an inorganic acid is insufficient, and it is necessary touse a metal salt.

The average particle size of the graft copolymer (B-III) of the fourthinvention produced as described above using the rubbery polymer (A-III)having the above-described preferred average particle size and particlesize distribution is typically 150 to 600 nm, preferably 180 to 500 nm.

The average particle size of the graft copolymer (B-III) is measured bythe method described in the section of EXAMPLES below.

[Thermoplastic Resin Composition]

A thermoplastic resin composition of the fourth invention contains thegraft copolymer (B-III) of the fourth invention. The content of thegraft copolymer (B-III) in 100 parts by mass of the thermoplastic resincomposition is preferably 20 to 60 parts by mass. When the content ofthe graft copolymer (B-III) in the thermoplastic resin composition isless than 20 parts by mass, the amount of rubber is small, and theimpact resistance of a molded article obtained tends to be low. When thecontent of the graft copolymer (B-III) in the thermoplastic resincomposition is more than 60 parts by mass, the pigmentability andphysical property balance of a molded article obtained tend to be poor.

In view of the balance of impact resistance, color developability, andother physical properties, the content of the graft copolymer (B-III) in100 parts by mass of the thermoplastic resin composition of the fourthinvention is more preferably 30 to 40 parts by mass.

The thermoplastic resin composition of the fourth invention mayoptionally contain any other thermoplastic resin and additives.

Examples of other thermoplastic resins include one or two or more ofpolyvinyl chloride, polystyrene, acrylonitrile-styrene copolymers,styrene-acrylonitrile-N-phenylmaleimide copolymers,α-methylstyrene-acrylonitrile copolymers, polymethyl methacrylate,methyl methacrylate-styrene copolymers, polycarbonate, polyamide,polyesters such as polyethylene terephthalate and polybutyleneterephthalate, and polyphenylene ether-polystyrene composites. Of these,acrylonitrile-styrene copolymers are preferred from the viewpoint ofimpact resistance and flowability.

Examples of additives include colorants such as pigments and dyes,fillers (e.g., carbon black, silica, and titanium oxide), flameretardants, stabilizers, reinforcing agents, processing aids, heatstabilizers, antioxidants, weathering agents, release agents,plasticizers, and antistatic agents.

The thermoplastic resin composition of the fourth invention is producedby mixing and dispersing the graft copolymer (B-III) and, optionally,any other thermoplastic resin and additives by using a V-type blender, aHenschel mixer, or the like and melt-kneading the resulting mixture byusing, for example, a kneading machine such as an extruder, a Banburymixer, a pressure kneader, or a roller.

The order of mixing of components is not particularly limited as long asall the components are uniformly mixed.

[Molded Article]

A molded article of the fourth invention is obtained by molding thethermoplastic resin composition of the fourth invention and is excellentin impact resistance, molded appearance, and color developability.

The method for molding the thermoplastic resin composition of the fourthinvention is the same as the method for molding the thermoplastic resincomposition of the second invention, and the preferred molding method isalso the same.

The molded article of the fourth invention obtained by molding thethermoplastic resin composition of the fourth invention is excellent inimpact resistance, molded appearance, and color developability thus issuitable for automotive interior and exterior parts, office machines,household electrical appliances, building materials, etc.

Examples of industrial applications of the molded article of the fourthinvention obtained by molding the thermoplastic resin composition of thefourth invention include automotive parts, particularly, variousexterior and interior parts used without paint, building material partssuch as wall materials and window frames, tableware, toys, householdelectrical appliance parts such as cleaner housings, televisionhousings, and air-conditioner housings, interior materials, shipmaterials, and communication device housings.

EXAMPLES

Examples will be specifically described below. It should be noted thatthe present invention is not limited to the following examples.Hereinafter, “%” means “% by mass”, and “parts” means “parts by mass”.

Examples and Comparative Examples of First Invention [Methods ofMeasurements, Evaluations, and Operations]

Methods of various measurements, evaluations, and operations therefor inthe following Examples and Comparative Examples are as described below.

<Average Particle Size>

For the composite rubber-like polymer (A), the volume average particlesize (MV) measured using a Microtrac (“Nanotrac 150” available fromNikkiso Co., Ltd.) and pure water as a measurement solvent was used asan average particle size.

<Refractive Index>

The refractive index of the composite rubber-like polymer (A) and thethermoplastic resin (D) was measured at 23° C. using an Abberefractometer “KPR-30A” available from Shimadzu Corporation. Therefractive index of the composite rubber-like polymer (A) was measuredafter the composite rubber-like polymer (A) was recovered from anemulsion of the composite rubber-like polymer (A) by precipitation withisopropyl alcohol and dried.

<Melt Kneading 1-1>

The graft copolymer (C) and the thermoplastic resin (D) were mixedtogether, and 0.8 parts of carbon black (“#966B” available from MitsuiChemicals, Inc.) was mixed with 100 parts of the total amount of thegraft copolymer (C) and the thermoplastic resin (D). Using a twin-screwextruder (“PCM30” available from Ikegai Corp.) having a diameter of 30mm and equipped with a vacuum vent, melt kneading was performed at acylinder temperature of 200° C. to 260° C. and a reduced pressure of93.325 kPa to obtain a black-colored thermoplastic resin composition.After the melt kneading, pelletization was performed using a pelletizer(“Model SH pelletizer” available from Soukensya).

<Melt Kneading 1-2>

The graft copolymer (C) and the thermoplastic resin (D) were mixedtogether, and using a twin-screw extruder (“PCM30” available from IkegaiCorp.) having a diameter of 30 mm and equipped with a vacuum vent, meltkneading was performed at a cylinder temperature of 200° C. to 260° C.and a reduced pressure of 93.325 kPa to obtain a transparentthermoplastic resin composition. After the melt kneading, pelletizationwas performed using a pelletizer (“Model SH pelletizer” available fromSoukensya).

<Injection Molding 1-1>

Using the pellets of the thermoplastic resin compositions obtained inMelt Kneading 1-1 and/or Melt Kneading 1-2, a molded article 80 mm long,10 mm wide, and 4 mm thick was molded with an injection molding machine(“IS55FP-1.5A” available from Toshiba Machine Co., Ltd.) under theconditions of a cylinder temperature of 200° C. to 270° C. and a moldtemperature of 60° C. and used as a molded article for Charpy impacttesting.

<Injection Molding 1-2>

Using the pellets of the thermoplastic resin compositions obtained inMelt Kneading 1-1 and/or Melt Kneading 1-2, molded articles 100 mm long,100 mm wide, and 2 mm thick were molded with an injection moldingmachine (“IS55FP-1.5A” available from Toshiba Machine Co., Ltd.) underthe conditions of a cylinder temperature of 200° C. to 270° C. and amold temperature of 60° C. and used as a molded article for colordevelopability evaluation, a molded article for transparency evaluation,and a molded article for weather resistance evaluation.

<Color Developability>

The molded article for color developability evaluation molded using theblack-colored thermoplastic resin composition obtained in Melt Kneading1-1 was measured for lightness L* by the SCE method using aspectrocolorimeter (“CM-3500d” available from Konica Minolta Optics,Inc). The measured L* is defined as “L* (ma)”. The lower the L*, theblacker the molded article and the better the color developability.

“Lightness (L*)” means a lightness value (L*) among color values in theL*a*b* color system employed in JIS Z 8729.

The “SCE method” means a method for measuring color by using aspectrocolorimeter in accordance with JIS Z 8722 with specularreflection being removed by light trapping.

<Transparency>

The haze value (Hz) of the molded article for transparency evaluationmolded using the transparent thermoplastic resin composition obtained inMelt Kneading 1-2 was measured with a haze meter (available fromMurakami Color Research Laboratory Co., Ltd). The smaller the haze, thehigher the transparency.

<Weather Resistance>

In the case of the molded article for weather resistance evaluationmolded using the black-colored thermoplastic resin composition obtainedin Melt Kneading 1-1, the molded article for weather resistanceevaluation was treated for 1500 hours using a Sunshine Weather Meter(available from Suga Test Instruments Co., Ltd.) under the conditions ofa black panel temperature of 63° C. and a cycle of 60 minutes (rainfall:12 minutes). The degree of change in color (ΔE) before and after thetreatment was measured with a spectrocolorimeter (“CM-3500d” availablefrom Konica Minolta Optips, Inc.) and evaluated. The smaller the ΔE, thebetter the weather resistance.

In the case of the molded article for weather resistance evaluationmolded using the transparent thermoplastic resin composition obtained inMelt Kneading 1-2, the molded article for weather resistance evaluationwas treated for 1500 hours using a Sunshine Weather Meter (availablefrom Suga Test Instruments Co., Ltd.) under the conditions of a blackpanel temperature of 63° C. and a cycle of 60 minutes (rainfall: 12minutes). The change in haze (ΔHz) before and after the treatment wasmeasured with a haze meter (available from Murakami Color ResearchLaboratory Co., Ltd). The smaller the ΔHz, the better the weatherresistance.

<Impact Resistance>

The Charpy impact strength of the molded article for Charpy impacttesting was measured by performing a Charpy impact test (unnotched)under the condition of 23° C. in accordance with ISO 179 standard. TheCharpy impact strength of a molded article obtained using anacrylonitrile-styrene copolymer resin, i.e., a thermoplastic resin (D2)described below was measured by a notched Charpy impact test.

[Production of Graft Copolymers]

Production Example 1-1: Graft Polymer (C1) <<Production of CompositeRubber-Like Polymer (A1)>>

Twenty four parts of polymethylphenyl siloxane “HIVAC-F-5” (refractiveindex: 1.575, viscosity: 160 mm²/s) available from Shin-Etsu ChemicalCo., Ltd., 75 parts of n-butyl acrylate, 1 part of allyl methacrylatewere mixed together to obtain a mixture (Ac1). While stirring themixture obtained, 310 parts of deionized water, 1 part of dipotassiumalkenyl succinate, 0.1 parts of t-butyl hydroperoxide, and 2.5 parts ofhexadecane, ultrasonic irradiation was performed at an amplitude of 35μm for 20 minutes using an “ULTRASONIC HOMOGENIZER US-600” availablefrom Nihonseiki Kaisha Ltd. to obtain a miniemulsion of the mixture(Ac1).

The miniemulsion of the mixture (Ac1) was loaded into a reaction vesselequipped with a reagent injector, a condenser, a jacket heater, and astirring device. The reaction vessel was purged with nitrogen, and thetemperature was then raised to 55° C. Next, 0.3 parts of Rongalite,0.0001 parts of ferrous sulfate heptahydrate, 0.0003 parts of disodiumethylenediaminetetraacetate, and 10 parts of deionized water were addedto initiate polymerization. After polymerization exotherm was observed,the jacket temperature was set at 75° C., and the polymerization wascontinued until polymerization exotherm was not observed anymore. Theresultant was further maintained for 1 hour to obtain an emulsion of acomposite rubber-like polymer (A1). The volume average particle size ofthe emulsion of the composite rubber-like polymer (A1) was 122 nm.

<<Production of Graft Copolymer (C1)>>

To the emulsion (solid content: 50 parts) of the composite rubber-likepolymer (A1), an aqueous solution of 0.0002 parts of ferrous sulfateheptahydrate, 0.0006 parts of disodium ethylenediaminetetraacetate, and0.25 parts of Rongalite in 10 parts of ion-exchanged water was added.Next, while adding dropwise 49.2 parts of methyl methacrylate, 0.8 partsof methyl acrylate, and 0.2 parts of t-butyl hydroperoxide over 100minutes, graft polymerization was performed at 75° C. Next, 150 parts ofan aqueous solution in which calcium acetate was dissolved in aproportion of 5% were heated to 60° C., and while stirring the aqueoussolution, the emulsion obtained was gradually added dropwise thereto tobe coagulated. The coagulation obtained was separated, washed, and thendried to obtain a dry powder of a graft copolymer (C1).

Production Example 1-2: Graft Polymer (C2)

A composite rubber-like polymer (A2) and a graft polymer (C2) wereobtained by performing the reaction under the same reaction conditionsas in Production Example 1-1 except that 66.3 parts of polymethylphenylsiloxane “KF-54” (refractive index: 1.505, viscosity: 400 mm²/s)available from Shin-Etsu Chemical Co., Ltd., 32.7 parts of n-butylacrylate, and 1 part of allyl methacrylate were used in place of 24parts of polymethylphenyl siloxane “HIVAC F-5” available from Shin-EtsuChemical Co., Ltd., 75 parts of n-butyl acrylate, and 1 part of allylmethacrylate. The volume average particle size of the compositerubber-like polymer (A2) was 125 nm.

Production Example 1-3: Graft Polymer (C3)

A composite rubber-like polymer (A3) and a graft polymer (C3) wereobtained by performing the reaction under the same reaction conditionsas in Production Example 1-1 except that ultrasonic irradiation wasperformed at an amplitude of 20 μm for 20 minutes using an “ULTRASONICHOMOGENIZER US-600” available from Nihonseiki Kaisha Ltd. The volumeaverage particle size of the composite rubber-like polymer (A3) was 282nm.

Production Example 1-4: Graft Polymer (C4) <<Production of CompositeRubber-Like Polymer (A4)>>

Twenty four parts of polymethylphenyl siloxane “HIVAC F-5” availablefrom Shin-Etsu Chemical Co., Ltd., 75 parts of n-butyl acrylate, 1 partof allyl methacrylate, and 0.1 parts of t-butyl hydroperoxide were mixedtogether. The resulting mixture, 310 parts of deionized water, and 1part of dipotassium alkenyl succinate were loaded into a reaction vesselequipped with a reagent injector, a condenser, a jacket heater, and astirring device. The reaction vessel was purged with nitrogen, and thetemperature was then raised to 55° C. Next, 0.3 parts of Rongalite,0.0001 parts of ferrous sulfate heptahydrate, 0.0003 parts of disodiumethylenediaminetetraacetate, and 10 parts of deionized water were addedto initiate polymerization. After polymerization exotherm was observed,the jacket temperature was set at 75° C., and the polymerization wascontinued until polymerization exotherm was not observed anymore. Theresultant was further maintained for 1 hour and filtered through a200-mesh wire net to obtain an emulsion of a composite rubber-likepolymer (A4). When the reaction vessel after the reaction was inspected,a large amount of oily deposit was observed, demonstrating that thepolymethylphenyl siloxane “HIVAC F-5” was not sufficiently combined inthe composite rubber-like polymer (A4). The volume average particle sizeof the composite rubber-like polymer (A4) was 102 nm.

<<Production of Graft Polymer (C4)>>

A graft polymer (C4) was obtained in the same manner as in ProductionExample 1-1 except that the composite rubber-like polymer (A4) was usedin place of the composite rubber-like polymer (A1).

Production Example 1-5: Graft Polymer (C5) <<Production of CompositeRubber-Like Polymer (A5)>>

While stirring 24 parts of polymethylphenyl siloxane “HIVAC F-5”available from Shin-Etsu Chemical Co., Ltd., 310 parts of deionizedwater, and 1 part of dipotassium alkenyl succinate, ultrasonicirradiation was performed at an amplitude of 35 μm for 20 minutes usingan “ULTRASONIC HOMOGENIZER US-600” available from Nihonseiki Kaisha Ltd.

Next, the resulting polymethylphenyl siloxane emulsion, 0.3 parts ofRongalite, 0.0001 parts of ferrous sulfate heptahydrate, and 0.0003parts of disodium ethylenediaminetetraacetate were loaded into areaction vessel equipped with a reagent injector, a condenser, a jacketheater, and a stirring device, and the reaction vessel was purged withnitrogen. After the temperature was raised to 70° C., polymerization wasperformed while adding dropwise 75 parts of n-butyl acrylate, 1 part ofallyl methacrylate, and 0.1 parts of t-butyl hydroperoxide for 60minutes. Next, the jacket temperature was set at 75° C. and furthermaintained for 1 hour to obtain an emulsion of a composite rubber-likepolymer (A5). The volume average particle size of the emulsion of thecomposite rubber-like polymer (A5) was 142 nm.

<<Production of Graft Polymer (C5)>>

A graft polymer (C5) was obtained in the same manner as in ProductionExample 1-1 except that the composite rubber-like polymer (A5) was usedin place of the composite rubber-like polymer (A1).

Production Example 1-6: Graft Polymer (C6)

A composite rubber-like polymer (A6) and a graft polymer (C6) wereobtained by performing the reaction under the same conditions as inProduction Example 1-5 except that the addition amount of dipotassiumalkenyl succinate was 0.7 parts and the amplitude of the “ULTRASONICHOMOGENIZER US-600” available from Nihonseiki Kaisha Ltd. was 20 μm. Thevolume average particle size of the composite rubber-like polymer (A6)was 302 nm.

<Graft Polymer (C7)>

“MUX-60” available from UMG ABS, Ltd. was used as a graft polymer (C7)in which methyl methacrylate was graft-polymerized onto a compositerubber-like polymer of polybutadiene and n-butyl polyacrylate.

Production Example 1-7: Graft Polymer (C8)

A composite rubber-like polymer (A8) and a graft polymer (C8) wereobtained by performing the reaction under the same conditions as inProduction Example 1-1 except that in producing a composite rubber-likepolymer, 50 parts of polymethylphenyl siloxane “HIVAC F-5” availablefrom Shin-Etsu Chemical Co., Ltd., 49 parts of n-butyl acrylate, and 1part of allyl methacrylate were used in place of 24 parts ofpolymethylphenyl siloxane “HIVAC F-5” available from Shin-Etsu ChemicalCo., Ltd., 75 parts of n-butyl acrylate, and 1 part of allylmethacrylate, and in producing a graft copolymer, 49.2 parts of methylmethacrylate and 0.8 parts of methyl acrylate were changed to 35 partsof styrene and 15 parts of acrylonitrile. The volume average particlesize of the composite rubber-like polymer (A8) was 155 nm.

Production Example 1-8: Graft Polymer (C9)

A composite rubber-like polymer (A9) and a graft polymer (C9) wereobtained by performing the reaction under the same conditions as inProduction Example 1-1 except that in producing a composite rubber-likepolymer, 14 parts of polydimethylsiloxane “KF-96-500cs” (refractiveindex: 1.403, viscosity: 500 mm²/s) available from Shin-Etsu ChemicalCo., Ltd., 35 parts of n-butyl acrylate, and 1 part of allylmethacrylate were used in place of 24 parts of polymethylphenyl siloxane“HIVAC F-5” available from Shin-Etsu Chemical Co., Ltd., 75 parts ofn-butyl acrylate, and 1 part of allyl methacrylate, and in producing agraft copolymer, 49.2 parts of methyl methacrylate, 0.8 parts of methylacrylate were changed to 35 parts of styrene and 15 parts ofacrylonitrile. The volume average particle size of the compositerubber-like polymer (A9) was 111 nm.

Production Example 1-9: Graft Polymer (C10)

A composite rubber-like polymer (A10) and a graft polymer (C10) wereobtained by performing the reaction under the same conditions as inProduction Example 1-5 except that in producing a composite rubber-likepolymer, 14 parts of polydimethylsiloxane “KF-96-500cs” available fromShin-Etsu Chemical Co., Ltd., 35 parts of n-butyl acrylate, and 1 partof allyl methacrylate were used in place of 24 parts of polymethylphenylsiloxane “HIVAC F-5” available from Shin-Etsu Chemical Co., Ltd., 75parts of n-butyl acrylate, and 1 part of allyl methacrylate, and inproducing a graft copolymer, 49.2 parts of methyl methacrylate, 0.8parts of methyl acrylate were changed to 35 parts of styrene and 15parts of acrylonitrile. The volume average particle size of thecomposite rubber-like polymer (A10) was 138 nm.

Production Example 1-10: Graft Polymer (C11)

A graft polymer (C11) was obtained in the same manner as in ProductionExample 1-1 except that the composite rubber-like polymer (A8) was usedin place of the composite rubber-like polymer (A1).

Production Example 1-11: Graft Polymer (C12)

A composite rubber-like polymer (A12) and a graft polymer (C12) wereobtained by performing the reaction under the same conditions as inProduction Example 1-1 except that in producing a composite rubber-likepolymer, 8 parts of polymethylphenyl siloxane “HIVAC F-5” available fromShin-Etsu Chemical Co., Ltd., 91 parts of n-butyl acrylate, and 1 partof allyl methacrylate were used in place of 24 parts of polymethylphenylsiloxane “HIVAC F-5” available from Shin-Etsu Chemical Co., Ltd., 75parts of n-butyl acrylate, and 1 part of allyl methacrylate. The volumeaverage particle size of the composite rubber-like polymer (A12) was 132nm.

[Production of Thermoplastic Resins]

Production Example 1-12: Thermoplastic Resin (D1)

Into a nitrogen-purged stainless steel reaction vessel equipped with astirrer, 150 parts of deionized water, 99 parts of methyl methacrylate,1 part of methyl acrylate, 0.2 parts of 2,2′-azobis(isobutyronitrile),0.25 parts of n-octyl mercaptan, 0.47 parts of calcium hydroxyapatite,and 0.003 parts of potassium alkenyl succinate were loaded. The innertemperature of the reaction vessel was set at 75° C., and the reactionwas allowed to proceed for 3 hours. The temperature was then raised to90° C., and the reaction was allowed to proceed for 1 hour. The contentswere extracted, washed with a centrifugal dehydrator, and dried toobtain a powdery thermoplastic resin (D1).

Production Example 1-13: Thermoplastic Resin (D2)

Into a nitrogen-purged stainless steel reaction vessel equipped with astirrer, 120 parts of deionized water, 0.47 parts of calciumhydroxyapatite, 0.003 parts of potassium alkenyl succinate, 0.3 parts of2,2′-azobis(isobutyronitrile), 30 parts of acrylonitrile, 70 parts ofstyrene, and 0.35 parts of t-dodecyl mercaptan were loaded. The startingtemperature was set at 75° C., and the reaction was allowed to proceedfor 5 hours. The temperature was then raised to 120° C., and thereaction was allowed to proceed for 2 hours. The contents were takenout, washed with a centrifugal dehydrator, and dried to obtain a powderythermoplastic resin (D2).

Production Example 1-14: Thermoplastic Resin (D3)

Into a nitrogen-purged stainless steel reaction vessel equipped with astirrer, 150 parts of deionized water, 82 parts of methyl methacrylate,12 parts of N-phenylmaleimide, 6 parts of styrene, 0.2 parts of2,2′-azobis(isobutyronitrile), 0.25 parts of n-octyl mercaptan, 0.67parts of calcium hydroxyapatite, and 0.003 parts of potassium alkenylsuccinate were loaded. The inner temperature of the reaction vessel wasset at 75° C., and the reaction was allowed to proceed for 3 hours. Thetemperature was then raised to 90° C., and the reaction was allowed toproceed for 1 hour. The contents were extracted, washed with acentrifugal dehydrator, and dried to obtain a powdery thermoplasticresin (D3).

Table 1 summarizes the volume average particle sizes and refractiveindices of the composite rubber-like polymers (A) used for the graftcopolymers (C) and the refractive index of the thermoplastic resins (D).

TABLE 1 Volume average particle size Refractive (nm) index Remarks Graftcopolymer (C1) Composite rubber-like polymer (A1) 122 1.494 Presentinvention example Graft copolymer (C2) Composite rubber-like polymer(A2) 125 1.492 Present invention example Graft copolymer (C3) Compositerubber-like polymer (A3) 282 1.492 Present invention example Graftcopolymer (C4) Composite rubber-like polymer (A4) 102 1.471 Comparativeexample Graft copolymer (C5) Composite rubber-like polymer (A5) 1421.496 Comparative example Graft copolymer (C6) Composite rubber-likepolymer (A6) 302 1.492 Comparative example Graft copolymer (C8)Composite rubber-like polymer (A8) 155 1.521 Present invention exampleGraft copolymer (C9) Composite rubber-like polymer (A9) 111 1.446Present invention example Graft copolymer (C10) Composite rubber-likepolymer (A10) 138 1.448 Comparative example Graft copolymer (C11)Composite rubber-like polymer (A8) 155 1.521 Present invention exampleGraft copolymer (C12) Composite rubber-like polymer (A12) 132 1.475Present invention example Thermoplastic resin (D1) — — 1.492 —Thermoplastic resin (D2) — — 1.569 — Thermoplastic resin (D3) — — 1.515—

Examples 1-1 to 1-5, Comparative Examples 1-1 to 1-5

The graft copolymer (C) and the thermoplastic resin (D1) in amountsshown in Table 2 were pelletized by the method of Melt Kneading 1-1described above, and molded articles were obtained by injection molding.The molded articles obtained were evaluated for color developability,weather resistance, and impact resistance. The results are shown inTable 2.

TABLE 2 Com- Exam- Exam- Exam- Exam- Exam- Comparative ComparativeComparative Comparative parative ple ple ple ple ple example exampleexample example example 1-1 1-2 1-3 1-4 1-5 1-1 1-2 1-3 1-4 1-5 AmountGraft C1 10 40 60 (parts) copolymer (C) C2 40 C3 40 C4 40 C5 40 C6 40 C740 Thermoplastic D1 90 60 40 60 60 60 60 60 60 100 resin (D) EvaluationColor L* 3.8 4.2 4.3 3.8 4.0 7.2 6.2 8.1 4.0 3.5 results developabilityWeather ΔE 0.5 1.0 1.1 0.9 1.1 1.0 1.1 1.3 9.6 0.5 resistance ImpactkJ/m² 22 53 82 57 65 33 55 66 78 17 resistance

As shown in Examples 1-1 to 1-5, the graft copolymers (C) of the firstinvention can provide thermoplastic resin compositions and moldedarticles thereof excellent in weather resistance, color developability,and impact resistance. By contrast, as shown in Comparative Examples 1-1to 1-3, the graft polymers polymerized without going throughminiemulsification of the mixture (Ac) and the thermoplastic resincompositions including the graft polymers have poor colordevelopability. As shown in Comparative Example 1-4, the use of a graftpolymer obtained by using polybutadiene instead of polyorganosiloxane ina composite rubber-like polymer results in poor weather resistance.Comparative Example 1-5 is poor in impact resistance because the graftcopolymer (C) is not included.

Examples 1-6 and 1-7, Comparative Example 1-6

The graft copolymer (C) and the thermoplastic resin (D2) in amountsshown in Table 3 were pelletized by the method of Melt Kneading 1-1described above, and molded articles were obtained by injection molding.The molded articles obtained were evaluated for color developability,weather resistance, and impact resistance. The results are shown inTable 3.

TABLE 3 Exam- Exam- Comparative ple ple example 1-6 1-7 1-6 Amount Graftcopolymer(C) C8 40 (parts) C9 40 C10 40 Thermoplastic D2 60 60 60 resin(D) Evalu- Color developability L* 4.8 5.5 7.2 ation Weather resistanceΔE 1.5 1.7 1.6 results Impact resistance kJ/m² 22 28 26

As shown in Examples 1-6 and 1-7, the graft copolymers (C) of the firstinvention can provide thermoplastic resin compositions and moldedarticles thereof excellent in weather resistance, color developability,and impact resistance. By contrast, as shown in Comparative Example 1-6,the thermoplastic resin composition including a graft polymerpolymerized without going through miniemulsification of the mixture (Ac)has poor color developability.

Examples 1-8 to 1-10, Comparative Example 1-7, Reference Example 1-1

The graft copolymer (C) and the thermoplastic resin (D1) or thethermoplastic resin (D3) in amounts shown in Table 4 were pelletized bythe method of Melt Kneading 1-2 described above, and molded articleswere obtained by injection molding. The molded articles obtained wereevaluated for color developability, transparency, weather resistance,and impact resistance. The results are shown in Table 4.

TABLE 4 Comparative Reference Example Example Example example Example1-8 1-9 1-10 1-7 1-1 Amount (parts) Graft copolymer (C) C1 40 C11 40 40C12 40 C5 40 Thermoplastic resin (D) D1 60 60 60 60 D3 60 Refractiveindex difference※ 0.002 0.006 0.017 0.004 0.029 Evaluation Colordevelopability L* 4.2 4.8 5.2 6.2 5.3 results Transparency Hz (%) 0.93.3 8.2 9.1 11.3 Weather resistance Δ Hz (%) 0.7 1.2 1.1 0.9 1.2 Impactresistance kJ/m² 53 48 51 55 60 ※Refractive index difference betweengraft copolymer (C) and thermoplastic resin (D)

As shown in Examples 1-8 to 1-10, when the refractive index differencebetween the graft copolymer (C) and the thermoplastic resin (D) is 0.02or less in the first invention, a thermoplastic resin composition and amolded article thereof that are highly transparent are provided. Bycontrast, as shown in Comparative Example 1-7, in the thermoplasticresin composition including a graft polymer polymerized without goingthrough miniemulsification of the mixture (Ac), the composition of thecomposite rubber-like polymer (A) is not uniform, and the transparencyis poor although the refractive index difference between the graftcopolymer (C) and the thermoplastic resin (D) is 0.02 or less.

Reference Example 1-1 is poor in transparency because the refractiveindex difference between the graft copolymer (C) and the thermoplasticresin (D) is more than 0.02 but is good in color developability, weatherresistance, and impact resistance.

Examples and Comparative Examples of Second Invention [Methods ofMeasurements and Evaluations]

Methods of various measurements, evaluations, and operations therefor inthe following Examples and Comparative Examples are as described below.

<Measurement of Number Average Molecular Weight (Mn)>

The number average molecular weight (Mn) in terms of polystyrene wasmeasured by GPC (GPC: “GPC/V2000” available from Waters, column: “ShodexAT-G+AT-806MS” available from Showa Denko K.K.) using o-dichlorobenzene(145° C.) as a solvent.

<Measurement of Average Particle Size>

The volume average particle size (MV) measured using a Microtrac(“Nanotrac 150” available from Nikkiso Co., Ltd.) and pure water as ameasurement solvent was used as an average particle size.

It was confirmed by electron microscopic image analysis that the averageparticle size of the crosslinked particles (A-I) dispersed in the graftcrosslinked particles (B-I) equated with the average particle size ofthe crosslinked particles (A-I) and the graft crosslinked particles(B-I) in a thermoplastic resin composition.

<Melt Kneading 2-1>

The crosslinked particles (A-I) or the graft crosslinked particles (B-I)and the thermoplastic resin (D-I) were mixed together, and using atwin-screw extruder (“PCM30” available from Ikegai Corp.) having adiameter of 30 mm and equipped with a vacuum vent, melt kneading wasperformed at a cylinder temperature of 200° C. to 260° C. and a reducedpressure of 93.325 kPa to obtain a transparent thermoplastic resincomposition. After the melt kneading, pelletization was performed usinga pelletizer (“Model SH pelletizer” available from Soukensya).

<Melt Kneading 2-2>

The crosslinked particles (A-I) or the graft crosslinked particles(B-I), the thermoplastic resin (D-I), and, furthermore, carbon black(“#966B” available from Mitsui Chemicals, Inc.) in an amount of 0.8parts relative to 100 parts of the total of the crosslinked particles(A-I) or the graft crosslinked particles (B-I) and the thermoplasticresin (D-I) were mixed together, and using a twin-screw extruder(“PCM30” available from Ikegai Corp.) having a diameter of 30 mm andequipped with a vacuum vent, melt kneading was performed at a cylindertemperature of 200° C. to 260° C. and a reduced pressure of 93.325 kPato obtain a black-colored thermoplastic resin composition. After themelt kneading, pelletization was performed using a pelletizer (“Model SHpelletizer” available from Soukensya).

<Measurement of Melt Volume Rate (MVR)>

The MVR of the thermoplastic resin composition obtained in Melt Kneading2-1 was measured in accordance with ISO 1133 standard. The MVR indicatesthe flowability of the thermoplastic resin composition.

<Injection Molding 2-1>

Using the pellets of the thermoplastic resin composition obtained inMelt Kneading 2-1, a molded article 80 mm long, 10 mm wide, and 4 mmthick was molded with an injection molding machine (“IS55FP-1.5A”available from Toshiba Machine Co., Ltd.) under the conditions of acylinder temperature of 200° C. to 270° C. and a mold temperature of 60°C. and used as a molded article for Charpy impact testing or a moldedarticle for tensile testing.

<Injection Molding 2-2>

Using the pellets of the thermoplastic resin composition obtained inMelt Kneading 2-2, molded articles 100 mm long, 100 mm wide, and 2 mmthick were molded with an injection molding machine (“IS55FP-1.5A”available from Toshiba Machine Co., Ltd.) under the conditions of acylinder temperature of 200° C. to 270° C. and a mold temperature of 60°C. and used as a molded article for color developability evaluation anda molded article for abrasion resistance evaluation.

<Evaluation of Impact Resistance>

The Charpy impact strength of the molded article for Charpy impacttesting was measured by performing a Charpy impact test (notched) underthe condition of 23° C. in accordance with ISO 179 standard.

<Evaluation of Color Developability>

The molded article for color developability evaluation was measured forlightness L* by the SCE method using a spectrocolorimeter (“CM-3500d”available from Konica Minolta Optips, Inc). The measured L* is definedas “L* (ma)”. The lower the L*, the blacker the molded article and thebetter the color developability.

“Lightness L*” means a lightness value (L*) among color values in theL*a*b* color system employed in JIS Z 8729.

The “SCE method” means a method for measuring color by using aspectrocolorimeter in accordance with JIS Z 8722 with specularreflection being removed by light trapping.

<Evaluation of Abrasion Resistance>

As shown in FIG. 1, a rod-like jig 2 having a tip portion 1 formed in asubstantially hemispherical shape was provided, and a laminate sheet Smade of eight pieces of gauze superposed on one another was put on thetip portion 1. The tip portion 1 having the laminate sheet S put thereonwas brought into contact with a surface of a molded article (test piece)M such that the rod-like jig 2 was perpendicular to the surface, and thetip portion 1 was slid on the surface of the molded article M in ahorizontal direction (an arrow X direction in the FIGURE) andreciprocated 100 times. During this process, a load of 1 kg was applied.After the 100 reciprocations, the lightness L* of the abraded surface ofthe molded article M was measured by the SCE method using aspectrocolorimeter similarly to the above-described evaluation of colordevelopability. The measured L* is defined as “L* (mc)”.

(Assessment of Abrasion Resistance)

ΔL*, which is a benchmark for assessing the prominence of abrasions onthe molded article M, was calculated from “L* (ma)” obtained in theabove-described evaluation of color developability and “L* (mc)” by thefollowing formula (5). Larger absolute values of ΔL*(mc−ma) indicatehigher prominence of abrasions.

ΔL*(mc−ma)=L*(mc)−L*(ma)  (5)

Evaluations were made by using the absolute value of ΔL*(mc−ma)according to the following criteria. In the case of A and B, it wasdetermined to have abrasion resistance.

A: The absolute value of ΔL*(mc−ma) is 2.0 or less. Abrasions are notprominent, and the design of a molded article is not impaired.

B: The absolute value of ΔL*(mc−ma) is more than 2.0 and 5.0 or less.Abrasions are less prominent, and the design of a molded article is notimpaired.

D: the absolute value of ΔL*(mc−ma) is more than 5.0. Abrasions areprominent, and the design of a molded article is impaired.

<Measurement of Mold Shrinkage Rate>

According to ASTM D 955, the molded article for tensile testing wasmeasured for its mold shrinkage rate from a mold dimension. The moldshrinkage rate is preferably 0.7% or less.

[Production of Di(Meth)Acrylic Acid Ester (a)]

Production Example 2-1: Di(Meth)Acrylic Acid Ester (a-1)

In a reaction vessel equipped with a distillator, 32.5 parts ofpolytetramethylene glycol (PTMG650; Mn, 650; available from MitsubishiChemical Corporation), 21.52 parts of methyl acrylate, 0.034 parts ofhydroquinone, 0.17 parts of tetrabutoxy titanium, and 250 parts oftoluene were placed and heated with stirring at a bath temperature of130° C. to 140° C. for 9 hours under atmospheric pressure under a streamof nitrogen. During this process, a liquid containing methanol wasdistilled by distillation. After the reaction, 3.0 parts of water wasadded to the reaction solution, and the resultant was stirred at a bathtemperature of 90° C. for 2 hours. Next, insoluble matter was removed bysuction filtration. Toluene was distilled off at 120° C. under reducedpressure, and low-boiling components (e.g., methyl acrylate and residualtoluene) were distilled off at 50 to 20 mmHg and a bath temperature of120° C. to 190° C. to obtain a colorless, transparent polytetramethyleneglycol diacrylate (di(meth)acrylic acid ester (a-1)). The number averagemolecular weight (Mn) of the di(meth)acrylic acid ester (a-1) measuredby GPC was 670.

Production Example 2-2: Di(Meth)Acrylic Acid Ester (a-2)

A colorless, transparent polytetramethylene glycol diacrylate(di(meth)acrylic acid ester (a-2)) was obtained in the same manner as inProduction Example 2-1 except that 42.5 parts of polytetramethyleneglycol (PTMG850; Mn, 850; available from Mitsubishi ChemicalCorporation) were used as polytetramethylene glycol. The number averagemolecular weight (Mn) of the di(meth)acrylic acid ester (a-2) measuredby GPC was 860.

Production Example 2-3: Di(Meth)Acrylic Acid Ester (a-3)

A colorless, transparent polytetramethylene glycol diacrylate(di(meth)acrylic acid ester (a-3)) was obtained in the same manner as inProduction Example 2-1 except that 50.0 parts of polytetramethyleneglycol (PTMG1000; Mn, 1000; available from Mitsubishi ChemicalCorporation) were used as polytetramethylene glycol. The number averagemolecular weight (Mn) of the di(meth)acrylic acid ester (a-3) measuredby GPC was 1010.

Production Example 2-4: Di(Meth)Acrylic Acid Ester (a-4)

A colorless, transparent polytetramethylene glycol diacrylate(di(meth)acrylic acid ester (a-4)) was obtained in the same manner as inProduction Example 2-1 except that 75.0 parts of polytetramethyleneglycol (PTMG1500; Mn, 1500; available from Mitsubishi ChemicalCorporation) were used as polytetramethylene glycol. The number averagemolecular weight (Mn) of the di(meth)acrylic acid ester (a-4) measuredby GPC was 1560.

Production Example 2-5: Di(Meth)Acrylic Acid Ester (a-5)

A colorless, transparent polytetramethylene glycol diacrylate(di(meth)acrylic acid ester (a-5)) was obtained in the same manner as inProduction Example 2-1 except that 100.0 parts of polytetramethyleneglycol (PTMG2000; Mn, 2000; available from Mitsubishi ChemicalCorporation) were used as polytetramethylene glycol. The number averagemolecular weight (Mn) of the di(meth)acrylic acid ester (a-5) measuredby GPC was 2070.

Production Example 2-6: Di(Meth)Acrylic Acid Ester (a-6)

A colorless, transparent polytetramethylene glycol diacrylate(di(meth)acrylic acid ester (a-6)) was obtained in the same manner as inProduction Example 2-1 except that 150.0 parts of polytetramethyleneglycol (PTMG3000; Mn, 3000; available from Mitsubishi ChemicalCorporation) were used as polytetramethylene glycol. The number averagemolecular weight (Mn) of the di(meth)acrylic acid ester (a-6) measuredby GPC was 3020.

Production Example 2-7: Di(Meth)Acrylic Acid Ester (a-7)

A white polyethylene glycol diacrylate (di(meth)acrylic acid ester(a-7)) was obtained in the same manner as in Production Example 2-1except that 300.0 parts of polyethylene glycol (PEG6000; Mn, 6000;available from TOHO Chemical Industry Co., Ltd.) were used in place ofpolytetramethylene glycol. The number average molecular weight (Mn) ofthe di(meth)acrylic acid ester (a-7) measured by GPC was 6040.

Production Example 2-8: Di(Meth)Acrylic Acid Ester (a-8)

A white polyethylene glycol diacrylate (di(meth)acrylic acid ester(a-8)) was obtained in the same manner as in Production Example 2-1except that 400.0 parts of polyethylene glycol (PEG8000; Mn, 8000;available from MP Biomedicals) were used in place of polytetramethyleneglycol. The number average molecular weight (Mn) of the di(meth)acrylicacid ester (a-8) measured by GPC was 8010.

Production Example 2-9: Di(Meth)Acrylic Acid Ester (a-9)

A white polyethylene glycol diacrylate (di(meth)acrylic acid ester(a-9)) was obtained in the same manner as in Production Example 2-1except that 500.0 parts of polyethylene glycol (PEG10000; Mn, 10000;available from TOHO Chemical Industry Co., Ltd.) were used in place ofpolytetramethylene glycol. The number average molecular weight (Mn) ofthe di(meth)acrylic acid ester (a-9) measured by GPC was 10040.

Production Example 2-10: Di(Meth)Acrylic Acid Ester (a-10)

A colorless, transparent polycaprolactone diol diacrylate(di(meth)acrylic acid ester (a-10)) was obtained in the same manner asin Production Example 2-1 except that 100.0 parts of polycaprolactonediol (PRAXEL 220N; Mn, 2000; available from Daicel Corporation) wereused in place of polytetramethylene glycol. The number average molecularweight (Mn) of the di(meth)acrylic acid ester (a-10) measured by GPC was2040.

Production Example 2-11: Di(Meth)Acrylic Acid Ester (a-11)

A colorless, transparent polycarbonate diol diacrylate (di(meth)acrylicacid ester (a-11)) was obtained in the same manner as in ProductionExample 2-1 except that 100.0 parts of polycarbonate diol (UH-200; Mn,2000; available from Ube Industries, Ltd.) were used in place ofpolytetramethylene glycol. The number average molecular weight (Mn) ofthe di(meth)acrylic acid ester (a-11) measured by GPC was 2020.

Production Example 2-12: Di(Meth)Acrylic Acid Ester (a-12)

A colorless, transparent polytetramethylene glycol dimethacrylate(di(meth)acrylic acid ester (a-12)) was obtained in the same manner asin Production Example 2-1 except that 150.0 parts of polytetramethyleneglycol (PTMG3000; Mn, 3000; available from Mitsubishi ChemicalCorporation) were used as polytetramethylene glycol and 25.02 parts ofmethyl methacrylate were used in place of methyl acrylate. The numberaverage molecular weight (Mn) of the di(meth)acrylic acid ester (a-12)measured by GPC was 3020.

The component composition and number average molecular weight (Mn) ofthe di(meth)acrylic acid esters (a-1) to (a-12) obtained in ProductionExamples 2-1 to 2-12 are summarized in Table 5 below.

TABLE 5 Di(meth)acrylic X source (Meth)acrylic acid ester Diol Mn acidester Mn Remark a-1 Polytetramethylene 650 Methyl acrylate 670 Forglycol comparison a-2 Polytetramethylene 850 Methyl acrylate 860 Presentglycol invention example a-3 Polytetramethylene 1000 Methyl acrylate1010 Present glycol invention example a-4 Polytetramethylene 1500 Methylacrylate 1560 Present glycol invention example a-5 Polytetramethylene2000 Methyl acrylate 2070 Present glycol invention example a-6Polytetramethylene 3000 Methyl acrylate 3020 Present glycol inventionexample a-7 Polyethylene glycol 6000 Methyl acrylate 6040 Presentinvention example a-8 Polyethylene glycol 8000 Methyl acrylate 8010Present invention example a-9 Polyethylene glycol 10000 Methyl acrylate10040 For comparison a-10 Polycaprolactone 2000 Methyl acrylate 2040Present diol invention example a-11 Polycarbonate diol 2000 Methylacrylate 2020 Present invention example a-12 Polytetramethylene 3000Methyl 3020 Present glycol methacrylates invention example

[Production of Crosslinked Particles (A-I) or Graft CrosslinkedParticles (B-I)]

Production Example 2-13: Crosslinked Particles (A-I-1)

Forty parts of styrene, 20 parts of acrylonitrile, 310 parts ofdeionized water, 1 part of dipotassium alkenyl succinate, 0.2 parts oft-butyl hydroperoxide, and 2.5 parts of hexadecane were added to 40parts of the di(meth)acrylic acid ester (a-1). While stirring themixture, ultrasonic irradiation was performed using an ULTRASONICHOMOGENIZER available from Nihonseiki Kaisha Ltd. at an amplitude outputof 80% for 20 minutes to obtain a miniemulsion of astyrene-acrylonitrile solution in which the di(meth)acrylic acid ester(a-1) was dissolved.

The miniemulsion of the styrene-acrylonitrile solution in which thedi(meth)acrylic acid ester (a-1) was dissolved was loaded into areaction vessel equipped with a reagent injector, a condenser, a jacketheater, and a stirring device. The reaction vessel was purged withnitrogen, and the temperature was then raised to 55° C. Next, 0.3 partsof sodium formaldehyde sulfoxylate, 0.0001 parts of ferrous sulfateheptahydrate, 0.0003 parts of disodium ethylenediaminetetraacetate, and10 parts of deionized water were added to initiate polymerization. Afterpolymerization exotherm was observed, the jacket temperature was set at80° C., and the polymerization was continued until polymerizationexotherm was not observed anymore. The resultant was further maintainedfor 1 hour to obtain a water dispersion of crosslinked particles(A-I-1). The volume average particle size of the crosslinked particles(A-I-1) measured using the water dispersion of the crosslinked particles(A-I-1) was 0.15 μm. Next, the water dispersion of the crosslinkedparticles (A-I-1) was coagulated using 5% sulfuric acid, washed withwater, and dried to obtain the crosslinked particles (A-I-1).

Production Example 2-14: Crosslinked Particles (A-I-2) to (A-I-13)

Crosslinked particles (A-I-2) to (A-I-13) were obtained in the samemanner as in Production Example 2-13 except that the di(meth)acrylicacid esters (a-2) to (a-12) were used in place of the di(meth)acrylicacid ester (a-1) and the monomer compositions shown in Table 6 wereused.

The volume average particle size of the crosslinked particles (A-I-1) to(A-I-13) is shown in Table 6.

TABLE 6 Crosslinked particles A-I- A-I- A-I- A-I- A-I-1 A-I-2 A-I-3A-I-4 A-I-5 A-I-6 A-I-7 A-I-8 A-I-9 10 11 12 13 Monomer Type and (a-1)Mn = 670 40 com- Mn of (a-2) Mn = 860 40 position di(meth)acrylic (a-3)Mn = 1010 40 (parts) acid ester (a-4) Mn = 1560 40 (a-5) Mn = 2070 40(a-6) Mn = 3020 40 40 (a-7) Mn = 6040 40 (a-8) Mn = 8010 40 (a-9) Mn =10040 40 (a-10) Mn = 2040 40 (a-11) Mn = 2020 40 (a-12) Mn = 3020 40Styrene 40 40 40 40 40 40 40 40 40 40 40 40 45 Acrylonitrile 20 20 20 2020 20 20 20 20 20 20 20 15 Volume average particle size (μm) 0.15 0.150.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 Remarks ForPresent invention example For Present invention example com- comparisonparison

Production Example 2-15: Graft Crosslinked Particles (B-I-1)

A water dispersion (70 parts on a solids basis) of the crosslinkedparticles (A-I-6) was placed in a stainless steel polymerization tankequipped with a stirrer, and 0.4 parts of potassium alkenyl succinate,0.002 parts of ferrous sulfate heptahydrate, 0.64 parts of sodiumaldehyde sulfoxide, and 0.006 parts of disodiumethylenediamine-N,N,N′,N′-tetracarboxylate were added. To the resultingmixture, a mixed solution of 20 parts of styrene, 10 parts ofacrylonitrile, and 0.45 parts of t-butyl hydroperoxide was added over100 minutes and maintained for 30 minutes to complete the reaction. Alatex of the reaction product was coagulated with an aqueous sulfuricacid solution, washed with water, and then dried to obtain graftcrosslinked particles (B-I-1). The volume average particle size of thewater dispersion was 0.15 μm, and the graft rate was 43%.

[Production of Thermoplastic Resins]

Production Example 2-16: Thermoplastic Resin (D-I-1)

Into a stainless steel polymerization tank equipped with a stirrer, 150parts of ion-exchanged water, 67 parts of styrene, 33 parts ofacrylonitrile, 0.2 parts of 2,2′-azobis(isobutyronitrile), 0.25 parts ofn-octyl mercaptan, 0.47 parts of calcium hydroxyapatite, and 0.003 partsof potassium alkenyl succinate were loaded. The inner temperature of thepolymerization tank was set at 75° C., and the reaction was allowed toproceed for 3 hours. The temperature was raised to 90° C., and thereaction was allowed to proceed for 1 hour. The contents were extracted,washed with a centrifugal dehydrator, and dried to obtain a powderythermoplastic resin (D-I-1).

Production Example 2-17: Thermoplastic Resin (D-I-2)

A powdery thermoplastic resin (D-I-2) was obtained in the same manner asin Production Example 2-16 except that 75 parts of styrene and 25 partsof acrylonitrile were used.

Production Example 2-18: Thermoplastic Resin (D-I-3)

A powdery thermoplastic resin (D-I-3) was obtained in the same manner asin Production Example 2-16 except that 54 parts of styrene, 26 parts ofacrylonitrile, and, furthermore, 20 parts of N-phenylmaleimide wereused.

[Other Thermoplastic Resins]

The following other thermoplastic resins were used.

Thermoplastic resin (D-I-4): AAS (ASA) resin (acrylic-rubber-dispersedAS resin) available from UMG ABS, Ltd; 5310

Thermoplastic resin (D-I-5): ABS resin (butadiene-rubber-dispersed ASresin) available from UMG ABS, Ltd; EX18A

Thermoplastic resin (D-I-6): AES resin(ethylene⋅α-olefin-rubber-dispersed AS resin) available from UMG ABS,Ltd; ESA30

Thermoplastic resin (D-I-7): polycarbonate available from MitsubishiEngineering-Plastics Corporation; Novarex 7025R

The monomer composition of the thermoplastic resins (D-I-1) to (D-I-7)is summarized in Table 7 below.

TABLE 7 Thermoplastic resin D-1-1 D-1-2 D-1-3 D-1-4 D-1-5 D-1-6 D-1-7Monomer Styrene 67 75 54 ASA ABS AES PC composition Acrylonitrile 33 2526 (parts) N-Phenylmaleimide 20

Examples 2-1 to 2-17, Comparative Examples 2-1 to 2-7

The crosslinked particles (A-I) or the graft crosslinked particles (B-I)and the thermoplastic resin (D-I) were used in amounts shown in Tables 8to 10 and pelletized by the method of Melt Kneading 2-1 or 2-2 describedabove, and molded articles were obtained by Injection Molding 2-1 or2-2. The MVR of the thermoplastic resin composition obtained in MeltKneading 2-1 was measured. The molded articles obtained were evaluatedfor impact resistance, color developability, abrasion resistance, andmold shrinkage rate. The results are shown in Tables 8 to 10.

TABLE 8 Example 2-1 2-2 2-3 2-4 2-5 2-6 2-7 2-8 2-9 2-10 2-11Thermoplastic resin Crosslinked A-I-2 30 composition particles (A-I)A-I-3 30 formulation (parts) A-I-4 30 A-I-5 30 A-I-6 30 A-I-7 30 A-I-830 A-I-10 30 A-I-11 30 A-I-12 30 A-I-13 30 Thermoplastic resin D-I-1 7070 70 70 70 70 70 70 70 70 (D-I) D-I-2 70 Evaluation MVR cm³/10 min 1010 12 12 15 9 8 15 15 15 17 results Impact resistance kJ/m² 5 7 10 12 1515 15 10 10 15 12 Color developability L* (ma) 4.2 4.2 4.2 4.2 4.2 6.46.5 7.1 5.1 7.1 4.2 Abrasion Resistance Δ L* (mc-ma) B B A A A A A B B AA Mold shrinkage rate 23° C. (%) 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.40.4

TABLE 9 Example 2-12 2-13 2-14 2-15 2-16 2-17 Thermoplastic resinCrosslinked particles A-I-6 30 10 10 10 composition (A-I) A-I-13 10formulation Graft crosslinked B-I-1 43 (parts) particles (B-I)Thermoplastic resin D-I-1 57 (D-I) D-I-3 70 D-I-4 90 D-I-5 90 D-I-6 90D-I-7 90 Evaluation MVR cm³/10 min 8 21 20 21 15 16 results Impactresistance kJ/m² 12 22 13 17 80 17 Color developability L* (ma) 5.5 5.44.5 5.5 3 4.2 Abrasion Resistance ΔL* (mc-ma) A A A A A A Mold shrinkagerate 23° C. (%) 0.4 0.5 0.6 0.7 0.7 0.3

TABLE 10 Comparative example 2-1 2-2 2-3 2-4 2-5 2-6 2-7 Thermoplasticresin Crosslinked particles A-I-1 30 composition (A-I) A-I-9 30formulation Thermoplastic resin D-I-1 70 70 100 (parts) (D-I) D-I-4 100D-I-5 100 D-I-6 100 D-I-7 100 Evaluation results MVR cm³/10 min 14 2 1020 18 19 1 Impact resistance kJ/m² 2 15 1 18 13 15 65 Colordevelopability L* (ma) 5 11 4.2 5.4 4.5 5.5 3 Abrasion Resistance ΔL*(mc-ma) C A C C C A C Mold shrinkage rate 23° C. (%) 0.4 0.5 0.4 0.5 0.60.8 0.7

As is clear from Tables 8 to 10, the thermoplastic resin compositions ofExamples 2-1 to 2-17 were excellent in flowability. The molded articlesobtained in Examples 2-1 to 2-17 were excellent in impact resistance,color developability, abrasion resistance, and mold shrinkage rate. Bycontrast, Comparative Examples 2-1 to 2-7, which did not meet therequirements of the second invention, were poor in any of flowability,and impact resistance, color developability, abrasion resistance, andmold shrinkage rate of the molded articles. Specifically, in ComparativeExample 2-1, in which crosslinked particles obtained using adi(meth)acrylic acid ester (a) having an Mn of less than 800 are used,impact resistance and abrasion resistance are poor. In ComparativeExample 2-2, in which crosslinked particles obtained using adi(meth)acrylic acid ester (a) having an Mn of more than 9,000 are used,flowability and color developability are poor. In Comparative Examples2-3 to 2-7, in each of which a thermoplastic resin alone is used and thecrosslinked particles (A-I) or the graft crosslinked particles (B-I) ofthe second invention is not used, there is a defect due to eachthermoplastic resin, and flowability, impact resistance, abrasionresistance, and mold shrinkage rate cannot be satisfied at the sametime.

These results show that the crosslinked particles (A-I) and the graftcrosslinked particles (B-I) of the second invention can improve theflowability, impact resistance, and abrasion resistance of athermoplastic resin without impairing its color developability and moldshrinkage rate and are suitable for use in applications such asautomotive interior and exterior parts, office machines, householdelectrical appliances, and building materials.

Examples and Comparative Examples of Third Invention [Methods ofMeasurements and Evaluations]

Methods of various measurements, evaluations, and operations therefor inthe following Examples and Comparative Examples are as described below.

<Measurement of Number Average Molecular Weight (Mn)>

The number average molecular weight (Mn) in terms of polystyrene wasmeasured by GPC (GPC: “GPC/V2000” available from Waters, column: “ShodexAT-G+AT-806MS” available from Showa Denko K.K.) using o-dichlorobenzene(145° C.) as a solvent.

<Measurement of Average Particle Size>

The volume average particle size (MV) measured using a Microtrac(“Nanotrac 150” available from Nikkiso Co., Ltd.) and pure water as ameasurement solvent was used as an average particle size.

It was confirmed by electron microscopic image analysis that the averageparticle size of the crosslinked particles (A-II) dispersed in the graftcrosslinked particles (B-II) equated with the average particle size ofthe crosslinked particles (A-II) and the graft crosslinked particles(B-II) in a thermoplastic resin composition.

<Mass Proportion of Agglomerates>

An aqueous dispersion was filtered through a 100-mesh stainless-steelwire net, and the residue on the mesh was washed with water and dried,after which the mass of the filtered solid residue was measured. Themass proportion of agglomerates in the aqueous dispersion was determinedby the following formula (6). This proportion is preferably as low aspossible for better process passability, and is preferably 0.3% or less.

Mass proportion of agglomerates (% by mass)=[mass (g) of filtered solidresidue/mass (g) of total solid content]×100  (6)

<Melt Kneading 3-1>

The crosslinked particles (A-II) or the graft crosslinked particles(B-II) and the thermoplastic resin (D-II) were mixed together, and usinga twin-screw extruder (“PCM30” available from Ikegai Corp.) having adiameter of 30 mm and equipped with a vacuum vent, melt kneading wasperformed at a cylinder temperature of 200° C. to 260° C. and a reducedpressure of 93.325 kPa to obtain a transparent thermoplastic resincomposition. Furthermore, after the melt kneading, pelletization wasperformed using a pelletizer (“Model SH pelletizer” available fromSoukensya).

<Melt Kneading 3-2>

The crosslinked particles (A-II) or the graft crosslinked particles(B-II), the thermoplastic resin (D-II), and, furthermore, carbon black(“#966B” available from Mitsui Chemicals, Inc.) in an amount of 0.8parts relative to 100 parts of the total of the crosslinked particles(A-II) or the graft crosslinked particles (B-II) and the thermoplasticresin (D-II) were mixed together, and using a twin-screw extruder(“PCM30” available from Ikegai Corp.) having a diameter of 30 mm andequipped with a vacuum vent, melt kneading was performed at a cylindertemperature of 200° C. to 260° C. and a reduced pressure of 93.325 kPato obtain a black-colored thermoplastic resin composition. Furthermore,after the melt kneading, pelletization was performed using a pelletizer(“Model SH pelletizer” available from Soukensya).

<Measurement of Melt Volume Rate (MVR)>

The MVR of the thermoplastic resin composition obtained in Melt Kneading3-1 was measured in accordance with ISO 1133 standard. The MVR indicatesthe flowability of the thermoplastic resin composition.

<Injection Molding 3-1>

Using the pellets of the thermoplastic resin composition obtained inMelt Kneading 3-1, a molded article 80 mm long, 10 mm wide, and 4 mmthick was molded with an injection molding machine (“IS55FP-1.5A”available from Toshiba Machine Co., Ltd.) under the conditions of acylinder temperature of 200° C. to 270° C. and a mold temperature of 60°C. and used as a molded article for Charpy impact testing.

<Injection Molding 3-2>

Using the pellets of the thermoplastic resin composition obtained inMelt Kneading 3-1, molded articles 100 mm long, 100 mm wide, and 2 mmthick were molded with an injection molding machine (“IS55FP-1.5A”available from Toshiba Machine Co., Ltd.) under the conditions of acylinder temperature of 200° C. to 270° C. and a mold temperature of 60°C. and used as a molded article for transparency evaluation and a moldedarticle for weather resistance evaluation.

Using the pellets of the thermoplastic resin composition obtained inMelt Kneading 3-2, molded articles 100 mm long, 100 mm wide, and 2 mmthick were molded with an injection molding machine (“IS55FP-1.5A”available from Toshiba Machine Co., Ltd.) under the conditions of acylinder temperature of 200° C. to 270° C. and a mold temperature of 60°C. and used as a molded article for color developability evaluation anda molded article for abrasion resistance evaluation.

<Evaluation of Impact Resistance>

The Charpy impact strength of the molded article for Charpy impacttesting was measured in the same manner as in the second invention.

<Evaluation of Color Developability>

The molded article for color developability evaluation was evaluated forcolor developability in the same manner as in the second invention.

<Evaluation of Abrasion Resistance>

By the method shown in FIG. 1, evaluation and assessment of abrasionresistance were made in the same manner as in the second invention.

<Evaluation of Weather Resistance>

Using a Sunshine Weather Meter (available from Suga Test InstrumentsCo., Ltd.), the molded article for weather resistance evaluation wastreated for 1000 hours under the conditions of a black panel temperatureof 63° C. and a cycle of 60 minutes (rainfall: 12 minutes). The degreeof change in color (ΔE) before and after the treatment was measured witha color difference meter and evaluated.

The smaller the ΔE, the better the weather resistance, and A and B wereassessed as having weather resistance.

A: 0 or more and less than 1. No change in color is observed, and thedesign of a molded article is not impaired.

B: 1 or more and less than 3. Practically no change in color isobserved, and the design of a molded article is not impaired.

C: 5 or more and less than 10. A slight change in color is observed, andthe design of a molded article is impaired.

D: 10 or more. A great change in color is observed, and the design of amolded article is impaired.

<Evaluation of Transparency>

The cloudiness (Haze) of the molded article for transparency evaluationwas measured using a Haze meter (available from Murakami Color ResearchLaboratory Co., Ltd). Lower cloudiness means higher transparency.

The transparency was evaluated according to the following criteria, andA and B were assessed as having transparency.

A: 0% or more and less than 5%

B: 5% or more and less than 10%

C: 10% or more and less than 30%

D: 30% or more

[Production of Di(Meth)Acrylic Acid Ester (a)]

Di(meth)acrylic acid esters (a-1) to (a-12) were produced in the samemanner as in Production Examples 2-1 to 2-12 of the second invention.The component composition and number average molecular weight (Mn) ofthe di(meth)acrylic acid esters (a-1) to (a-12) are as shown in Table 5in the second invention.

Production Example 3-1: Crosslinked Particles (A-II-1)

Fifty parts of methyl methacrylate, 10 parts of styrene, 310 parts ofdeionized water, 1 part of dipotassium alkenyl succinate, 0.2 parts oft-butyl hydroperoxide, and 2.5 parts of hexadecane were added to 40parts of the di(meth)acrylic acid ester (a-1). While stirring themixture, ultrasonic irradiation was performed using an ULTRASONICHOMOGENIZER available from Nihonseiki Kaisha Ltd. at an amplitude outputof 80% for 20 minutes to obtain a miniemulsion of a methyl methacrylatesolution in which the di(meth)acrylic acid ester (a-1) was dissolved.

The miniemulsion of the methyl methacrylate solution in which thedi(meth)acrylic acid ester (a-1) was dissolved was loaded into areaction vessel equipped with a reagent injector, a condenser, a jacketheater, and a stirring device. The reaction vessel was purged withnitrogen, and the temperature was then raised to 55° C. Next, 0.3 partsof sodium formaldehyde sulfoxylate, 0.0001 parts of ferrous sulfateheptahydrate, 0.0003 parts of disodium ethylenediaminetetraacetate, and10 parts of deionized water were added to initiate polymerization. Afterpolymerization exotherm was observed, the jacket temperature was set at80° C., and the polymerization was continued until polymerizationexotherm was not observed anymore. The resultant was further maintainedfor 1 hour to obtain a water dispersion of crosslinked particles(A-II-1). The volume average particle size of the crosslinked particles(A-II-1) measured using the water dispersion of the crosslinkedparticles (A-II-1) was 0.15 μm, and the mass proportion of agglomerateswas 0.001%. Next, the water dispersion of the crosslinked particles(A-II-1) was coagulated using 5% sulfuric acid, washed with water, anddried to obtain the crosslinked particles (A-II-1).

Production Example 3-2: Crosslinked Particles (A-II-2) to (A-II-12)

Crosslinked particles (A-II-2) to (A-II-12) were obtained in the samemanner as in Production Example 3-1 except that the di(meth)acrylic acidesters (a-2) to (a-12) were used in place of the di(meth)acrylic acidester (a-1) and the monomer compositions shown in Table 11 were used.

The mass proportion of agglomerates during production and volume averageparticle size of the crosslinked particles (A-II-1) to (A-II-12) areshown in Table 11.

TABLE 11 Crosslinked particles A-II-1 A-II-2 A-II-3 A-II-4 A-II-5 A-II-6Monomer Type and Mn of (a-1) Mn = 670 40 composition di(meth)acrylicacid (a-2) Mn = 860 40 (parts) ester (a-3) Mn = 1010 40 (a-4) Mn = 156040 (a-5) Mn = 2070 40 (a-6) Mn = 3020 40 (a-7) Mn = 6040 (a-8) Mn = 8010(a-9) Mn = 10040 (a-10) Mn = 2040 (a-11) Mn = 2020 (a-12) Mn = 3020Methyl methacrylate 50 50 50 50 50 50 Styrene 10 10 10 10 10 10 Volumeaverage particle size(μm) 0.15 0.15 0.15 0.15 0.15 0.15 Mass proportionof agglomerates(%) 0.001 0.001 0.001 0.001 0.001 0.001 Remarks ForPresent invention example comparison A-II- A-II- A-II- A-II-7 A-II-8A-II-9 10 11 12 Monomer Type and Mn of (a-1) Mn = 670 compositiondi(meth)acrylic acid (a-2) Mn = 860 (parts) ester (a-3) Mn = 1010 (a-4)Mn = 1560 (a-5) Mn = 2070 (a-6) Mn = 3020 (a-7) Mn = 6040 40 (a-8) Mn =8010 40 (a-9) Mn = 10040 40 (a-10) Mn = 2040 40 (a-11) Mn = 2020 40(a-12) Mn = 3020 40 Methyl methacrylate 50 50 50 40 60 50 Styrene 10 1010 20 10 Volume average particle size (μm) 0.15 0.15 0.15 0.15 0.15 0.15Mass proportion of agglomerates (%) 0.005 0.001 0.03 0.001 0.001 0.001Remarks Present For Present invention comparison invention exampleexample

Production Example 3-3: Crosslinked Particles (A-II-13) to (A-II-24)

Crosslinked particles (A-II-13) to (A-II-24) were obtained in the samemanner as in Production Example 3-1 except that the di(meth)acrylic acidester (a-6) was used in place of the di(meth)acrylic acid ester (a-1)and the monomer compositions shown in Table 12 were used.

The mass proportion of agglomerates during production and volume averageparticle size of the crosslinked particles (A-II-13) to (A-II-24) areshown in Table 12.

TABLE 12 Crosslinked particles A-II- A-II- A-II- A-II- A-II- A-II- A-II-A-II- A-II- A-II- A-II- A-II- 13 14 15 16 17 18 19 20 21 22 23 24Monomer Di(meth)acrylic 19 21 24 26 29 31 49 51 69 71 79 81 compositionacid ester(a-6) (parts) Mn = 3020 Methyl 76 74 70 67 63 61 38 35 13 10 119 methacrylate Styrene 5 5 6 7 8 8 13 14 18 19 20 Volume averageparticle 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15size (μm) Mass proportion of 0.001 0.001 0.001 0.001 0.001 0.001 0.0010.001 0.001 0.001 0.001 0.001 agglomerates (%) Remarks For Presentinvention example For com- comparison parison

Production Example 3-4: Crosslinked Particles (A-II-25)

A water dispersion of crosslinked particles (A-II-25) was obtained inthe same manner as in Production Example 3-1 except that 40 parts of thedi(meth)acrylic acid ester (a-6), 50 parts of methyl methacrylate, and 3parts of dipotassium alkenyl succinate were used and the amplitudeoutput of the ULTRASONIC HOMOGENIZER available from Nihonseiki KaishaLtd. was 90%. The volume average particle size of the crosslinkedparticles (A-II-25) was 0.06 μm, and the mass proportion of agglomerateswas 0.001%.

Production Example 3-5: Crosslinked Particles (A-II-26)

A water dispersion of crosslinked particles (A-II-26) was obtained inthe same manner as in Production Example 3-4 except that 2 parts ofdipotassium alkenyl succinate was used. The volume average particle sizeof the crosslinked particles (A-II-26) was 0.09 μm, and the massproportion of agglomerates 0.001%.

Production Example 3-6: Crosslinked Particles (A-II-27)

A water dispersion of crosslinked particles (A-II-27) was obtained inthe same manner as in Production Example 3-4 except that 0.4 parts ofdipotassium alkenyl succinate was used and the amplitude output of theULTRASONIC HOMOGENIZER available from Nihonseiki Kaisha Ltd. was 30%.The volume average particle size of the crosslinked particles (A-II-27)was 0.45 μm, and the mass proportion of agglomerates was 0.003%.

Production Example 3-7: Crosslinked Particles (A-II-28)

Into a reaction vessel equipped with a reagent injector, a condenser, ajacket heater, and a stirring device, 200 parts of deionized water, 2.1parts of potassium oleate, 4.2 parts of dioctyl sodium sulfosuccinate,0.003 parts of ferrous sulfate heptahydrate, 0.009 parts of sodiumethylenediaminetetraacetate, and 0.3 parts of sodium formaldehydesulfoxylate were loaded. The reaction vessel was purged with nitrogen,and the temperature was then raised to 60° C. Next, after 81.4 parts ofbutyl acrylate, 18.6 parts of acrylic acid, and 0.5 parts of cumenehydroperoxide were added dropwise over 2 hours, the reaction was furtherallowed to proceed for 2 hours to obtain a water dispersion of anacid-radical-containing copolymer.

A 5% aqueous solution of 2.4 parts of sodium pyrophosphate in 100 parts(on a solids basis) of a water dispersion of the crosslinked particles(A-II-6) was added into the reactor and thoroughly stirred, after which1.8 parts (on a solids basis) of the water dispersion of theacid-radical-containing copolymer was added. The mixture was stirred for30 minutes while maintaining the inner temperature at 30° C. to obtaincrosslinked particles (A-II-28) and a water dispersion thereof. Thevolume average particle size of the crosslinked particles (A-II-28) was0.57 μm, and the mass proportion of agglomerates was 0.01%.

Production Example 3-8: Crosslinked Particles (A-II-29)

After 0.15 parts of sodium dodecylbenzene sulfonate was added to 100parts (on a solids basis) of a water dispersion of the crosslinkedparticles (A-II-6), 30 parts of a 5% aqueous acetic acid solution wasadded dropwise over 30 minutes. After completion of the dropwiseaddition, a 10% aqueous sodium hydroxide solution was added dropwiseover 10 minutes to obtain a water dispersion of crosslinked particles(A-II-29). The volume average particle size of the crosslinked particles(A-II-29) was 0.88 μm, and the mass proportion of agglomerates was0.01%.

Production Example 3-9: Crosslinked Particles (A-II-30)

A water dispersion of crosslinked particles (A-II-30) was obtained inthe same manner as in Production Example 3-8 except that the amount of5% aqueous acetic acid solution used was 50 parts. The volume averageparticle size of the crosslinked particles (A-II-30) was 1.2 μm, and themass proportion of agglomerates was 0.04%.

Production Example 3-10: Crosslinked Particles (A-II-31)

After 0.15 parts of sodium dodecylbenzene sulfonate was added to 100parts (on a solids basis) of a water dispersion of the crosslinkedparticles (A-II-6), 30 parts of a 20% aqueous acetic acid solution wasadded dropwise over 40 minutes. After completion of the dropwiseaddition, a 10% aqueous sodium hydroxide solution was added dropwiseover 10 minutes to obtain a water dispersion of crosslinked particles(A-II-31). The volume average particle size of the crosslinked particles(A-II-31) was 2.1 μm, and the mass proportion of agglomerates was 0.05%.

Production Example 3-11: Crosslinked Particles (A-II-32)

A water dispersion of crosslinked particles (A-II-32) was obtained inthe same manner as in Production Example 3-1 except that 40 parts of thedi(meth)acrylic acid ester (a-12), 40 parts of n-butyl acrylate, and 20parts of styrene were used. The volume average particle size of thecrosslinked particles (A-II-32) was 0.15 μm, and the mass proportion ofagglomerates was 0.001%.

Production Example 3-12: Crosslinked Particles (A-II-33)

Into a reaction vessel equipped with a reagent injector, a condenser, ajacket heater, and a stirring device, 40 parts of the di(meth)acrylicacid ester (a-6), 50 parts of methyl methacrylate, 10 parts of styrene,310 parts of deionized water, 1 part of dipotassium alkenyl succinate,and 0.2 parts of t-butyl hydroperoxide were added. The reaction vesselwas purged with nitrogen, and the temperature was then raised to 55° C.Next, 0.3 parts of sodium formaldehyde sulfoxylate, 0.0001 parts offerrous sulfate heptahydrate, 0.0003 parts of disodiumethylenediaminetetraacetate, and 10 parts of deionized water were addedto initiate polymerization. After polymerization exotherm was observed,the jacket temperature was set at 80° C., and the polymerization wascontinued until polymerization exotherm was not observed anymore. Theresultant was further maintained for 1 hour to obtain a water dispersionof crosslinked particles (A-II-33). The volume average particle size ofthe crosslinked particles (A-II-33) was 0.47 μm, and the mass proportionof agglomerates was 2.5%.

The mass proportion of agglomerates during production and volume averageparticle size of the crosslinked particles (A-II-25) to (A-II-33) areshown in Tables 13 and 14.

TABLE 13 Crosslinked particles A-II- A-II- A-II- A-II- A-II- A-II- A-II-25 26 27 28 29 30 31 Monomer Di(meth)acrylic acid ester 40 40 40composition (a-6) (parts) Mn = 3020 Methyl methacrylate 50 50 50 Styrene10 10 10 Enlarged crosslinked particles 100 100 100 100 (A-II-6) Volumeaverage particle size 0.06 0.09 0.45 0.57 0.88 1.2 2.1 (μm) Massproportion of 0.001 0.001 0.001 0.01 0.01 0.04 0.05 agglomerates (%)Remarks For Present invention example For comparison comparison

TABLE 14 Crosslinked particles A-II-32 A-II-33 Monomer Di(meth)acrylicacid (a-6) 40 composition ester (a-12) 40 (parts) Methyl methacrylate 50n-Butyl acrylate 40 Styrene 20 10 Volume average particle size(μm) 0.150.47 Mass proportion of agglomerates(%) 0.001 2.5 Remarks Presentinvention example

Production Example 3-13: Graft Crosslinked Particles (B-II-1)

A water dispersion (70 parts on a solids basis) of the crosslinkedparticles (A-II-1) was placed in a stainless steel polymerization tankequipped with a stirrer, and 0.56 parts of potassium alkenyl succinate,0.003 parts of ferrous sulfate heptahydrate, 0.89 parts of sodiumaldehyde sulfoxide, and 0.008 parts of disodiumethylenediamine-N,N,N′,N′-tetracarboxylate were added. To the resultingmixture, a mixed solution of 29 parts of methyl methacrylate, 1 part ofmethyl acrylate, and 0.45 parts of t-butyl hydroperoxide was added over100 minutes and maintained for 30 minutes to complete the reaction. Alatex of the reaction product was coagulated with an aqueous sulfuricacid solution, washed with water, and then dried to obtain graftcrosslinked particles (B-II-1). The volume average particle size of thewater dispersion was 0.15 μm, the graft rate was 43%, and the massproportion of agglomerates was 0.02%.

Production Example 3-14: Graft Crosslinked Particles (B-II-2) to(B-II-33)

Graft crosslinked particles (B-II-2) to (B-II-33) were obtained in thesame manner as in Production Example 3-13 except that the type of thecrosslinked particles (A-II) was changed to the crosslinked particles(A-II-2) to (A-II-33) and the raw material compositions shown in Tables15 to 17 were used.

The graft rate, volume average particle size, and mass proportion ofagglomerates during production of the graft crosslinked particles(B-II-1) to (B-II-33) are shown in Tables 15 to 17.

TABLE 15 Graft crosslinked particles B-II- B-II- B-II- B-II- B-II- B-II-B-II- B-II- B-II- 1 2 3 4 5 6 B-II-7 B-II-8 B-II-9 10 11 12 Raw materialCrosslinked particles (A-II-1) 70 composition Crosslinked particles(A-II-2) 70 (parts) Crosslinked particles (A-II-3) 70 Crosslinkedparticles (A-II-4) 70 Crosslinked particles (A-II-5) 70 Crosslinkedparticles (A-II-6) 70 Crosslinked particles (A-II-7) 70 Crosslinkedparticles (A-II-8) 70 Crosslinked particles (A-II-9) 70 Crosslinkedparticles 70 (A-II-10) Crosslinked particles 70 (A-II-11) Crosslinkedparticles 70 (A-II-12) Methyl methacrylate 29 29 29 29 29 29 29 29 29 2929 29 Methyl acrylate 1 1 1 1 1 1 1 1 1 1 1 1 Graft rate (%) 43 43 43 4343 43 43 43 43 43 43 43 Volume average particle size (μm) 0.15 0.15 0.150.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 Proportion of agglomerates(%) 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 RemarksFor Present invention example For Present comparison comparisoninvention example

TABLE 16 Graft crosslinked particles B-II- B-II- B-II- B-II- B-II- B-II-B-II- B-II- B-II- B-II- B-II- B-II- 13 14 15 16 17 18 19 20 21 22 23 24Raw material Crosslinked particles (A-II-13) 70 composition Crosslinkedparticles (A-II-14) 70 (parts) Crosslinked particles (A-II-15) 70Crosslinked particles (A-II-16) 70 Crosslinked particles (A-II-17) 70Crosslinked particles (A-II-18) 70 Crosslinked particles (A-II-19) 70Crosslinked particles (A-II-20) 70 Crosslinked particles (A-II-21) 70Crosslinked particles (A-II-22) 70 Crosslinked particles (A-II-23) 70Crosslinked particles (A-II-24) 70 Methyl methacrylate 29 29 29 29 29 2929 29 29 29 29 29 Methyl acrylate 1 1 1 1 1 1 1 1 1 1 1 1 Graft rate (%)43 43 43 43 43 43 43 43 43 43 43 43 Volume average particle size (μm)0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15 Proportionof agglomerates (%) 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.020.02 0.02 Remarks For Present invention example For comparisoncomparison

TABLE 17 Graft crosslinked particles B-II- B-II- B-II- B-II- B-II- B-II-B-II- B-II- B-II- 25 26 27 28 29 30 31 32 33 Raw material Crosslinkedparticles(A-II-25) 70 composition Crosslinked particles(A-II-26) 70(parts) Crosslinked particles(A-II-27) 70 Crosslinked particles(A-II-28)70 Crosslinked particles(A-II-29) 70 Crosslinked particles(A-II-30) 70Crosslinked particles(A-II-31) 70 Crosslinked particles(A-II-32) 70Crosslinked particles(A-II-33) 70 Methyl methacrylate 29 29 29 29 29 2929 29 29 Methyl acrylate 1 1 1 1 1 1 1 1 1 Graft rate (%) 43 43 43 43 4343 43 43 43 Volume average particle size (μm) 0.06 0.09 0.45 0.57 0.881.2 2.1 0.15 0.47 Proportion of agglomerates (%) 0.02 0.02 0.02 0.020.02 0.02 0.02 0.02 0.02 Remarks For Present invention example ForPresent comparison comparison invention example

[Production of Thermoplastic Resins]

Production Example 3-15: Thermoplastic Resin (D-II-1)

Into a stainless steel polymerization tank equipped with a stirrer, 150parts of ion-exchanged water, 98 parts of methyl methacrylate, 2 partsof methyl acrylate, 0.2 parts of 2,2′-azobis(isobutyronitrile), 0.25parts of n-octyl mercaptan, 0.47 parts of calcium hydroxyapatite, and0.003 parts of potassium alkenyl succinate were loaded. The innertemperature of the polymerization tank was set at 75° C., and thereaction was allowed to proceed for 3 hours. The temperature was raisedto 90° C., and the reaction was allowed to proceed for 1 hour. Thecontents were extracted, washed with a centrifugal dehydrator, and driedto obtain a powdery thermoplastic resin (D-II-1).

Production Example 3-16: Thermoplastic Resin (D-II-2)

A powdery thermoplastic resin (D-II-2) was obtained in the same manneras in Production Example 3-15 except that 70 parts of methylmethacrylate, 10 parts of styrene, and 20 parts of N-phenylmaleimidewere used.

[Other Thermoplastic Resins]

The following other thermoplastic resins were used.

Thermoplastic resin (D-II-3): polycarbonate available from MitsubishiEngineering-Plastics Corporation; Novarex 7025R

Thermoplastic resin (D-II-4): AAS(ASA) resin (acrylic-rubber-dispersedAS resin) available from UMG ABS, Ltd; S310

The monomer composition of the thermoplastic resins (D-II-1) to (D-II-4)is summarized in Table 18 below.

TABLE 18 Thermoplastic resin D-II-1 D-II-2 D-II-3 D-II-4 Monomer Methylmethacrylate 98 70 PC ASA composition Methyl acrylate 2 (parts) Styrene10 N-Phenylmaleimide 20

Examples 3-1 to 3-38, Comparative Examples 3-1 to 3-7

The crosslinked particles (A-II) or the graft crosslinked particles(B-II) and the thermoplastic resin (D-II) were used in amounts shown inTables 19 to 24 and pelletized by the method of Melt Kneading 3-1 or 3-2described above, and molded articles were obtained by Injection Molding3-1 or 3-2. The MVR of the thermoplastic resin composition obtained inMelt Kneading 3-1 was measured. The molded articles obtained wereevaluated for impact resistance, color developability, abrasionresistance, and weather resistance. The results are shown in Tables 19to 24.

The thermoplastic resin compositions of Example 3-6 and ComparativeExample 3-2 were evaluated for transparency, and the results are shownin Table 25.

TABLE 19 Example 3-1 3-2 3-3 3-4 3-5 3-6 3-7 3-8 3-9 3-10 Thermoplasticresin Graft B-II-2 30 composition Crosslinked particles B-II-3 30formulation (parts) (B-II) B-II-4 30 B-II-5 30 B-II-6 30 B-II-7 30B-II-8 30 B-II-10 30 B-II-11 30 B-II-12 30 Thermoplastic resin D-II-1 7070 70 70 70 70 70 70 70 70 (D-II) Evaluation MVR cm³/10 min 9 9 9 9 9 97 9 9 9 results Impact resistance kJ/m² 5 7 8 9 10 10 10 8 8 10 Colordevelopability L* (ma) 2.1 2.1 2.1 2.1 2.1 3.3 3.8 2.5 2.1 2.2 AbrasionResistance ΔL* (mc-ma) B B A A A A A B B A Weather resistance ΔE A A A AA A A A A A

TABLE 20 Example 3-11 3-12 3-13 3-14 3-15 3-16 3-17 3-18 3-19 3-20Thermoplastic resin Graft B-II-14 30 composition Crosslinked particlesB-II-15 30 formulation (parts) (B-II) B-II-16 30 B-II-17 30 B-II-18 30B-II-19 30 B-II-20 30 B-II-21 30 B-II-22 30 B-II-23 30 Thermoplasticresin D-II-1 70 70 70 70 70 70 70 70 70 70 (D-II) Evaluation MVR cm³/10min 10 9 9 9 9 9 8 8 7 7 results Impact resistance kJ/m² 7 8 9 9 10 1010 10 11 11 Color developability L* (ma) 2.1 2.1 2.1 2.1 2.1 2.1 2.3 2.52.6 2.8 Abrasion Resistance ΔL* (mc-ma) B B A A A A A A A A Weatherresistance ΔE A A A A A A A A A A

TABLE 21 Example 3-21 3-22 3-23 3-24 3-25 Thermoplastic resin Graftcrosslinked B-II-26 30 composition particles B-II-27 30 formulation(parts) (B-II) B-II-28 30 B-II-29 30 B-II-30 30 Thermoplastic resinD-II-1 70 70 70 70 70 (D-II) Evaluation results MVR cm³/10 min 8 9 9 910 Impact resistance kJ/m² 6 10 11 11 12 Color developability L* (ma)2.1 2.6 2.8 2.9 3.5 Abrasion Resistance ΔL* (mc-ma) A A A A B Weatherresistance ΔE A A A A A

TABLE 22 Example 3-26 3-27 3-28 3-29 3-30 3-31 Thermoplastic resinCrosslinked particles A-II-6 21 composition (A-II) formulation (parts)Graft crosslinked B-II-6 30 30 10 particles B-II-32 30 (B-II) B-II-33 30Thermoplastic resin D-II-1 70 70 79 (D-II) D-II-2 70 D-II-3 70 D-II-4 90Evaluation results MVR cm³/10 min 8 9 8 8 15 9 Impact resistance kJ/m²20 8 9 50 20 9 Color developability L* (ma) 2.5 2.6 3.1 3.5 3.8 2.5Abrasion Resistance ΔL* (mc-ma) A B A A A A Weather resistance ΔE A A AB A A

TABLE 23 Example 3-32 3-33 3-34 3-35 3-36 3-37 3-38 Thermoplastic Graftcrosslinked B-II-6 10 17 25 29 55 80 95 resin particles(B-II)composition Thermoplastic resin D-II-1 90 83 75 71 45 20 5 formulation(D-II) (parts) Evaluation MVR cm³/10 min 10 10 9 9 8 8 7 results Impactresistance kJ/m² 5 7 8 8 10 10 11 Color developability L* (ma) 2.1 2.12.1 2.1 2.3 2.5 2.7 Abrasion Resistance ΔL* (mc-ma) B B A A A A AWeather resistance ΔE A A A A A A A

TABLE 24 Comparative example 3-1 3-2 3-3 3-4 3-5 3-6 3-7 Thermoplasticresin Graft crosslinked B-II-1 30 composition particles B-II-9 30formulation (parts) (B-II) B-II-13 30 B-II-24 30 B-II-25 30 B-II-31 30Thermoplastic resin D-II-1 70 70 70 70 70 70 (D-II) D-II-4 100Evaluation results MVR cm³/10 min 10 5 9 5 5 10 12 Impact resistancekJ/m² 2 10 4 12 2 15 15 Color developability L* (ma) 2.1 4.2 2.1 4.5 2.14.2 3.8 Abrasion Resistance ΔL* (mc-ma) D A C A A C D Weather resistanceΔE A A A A A A A

TABLE 25 Comparative Example example 3-6 3-2 Thermoplastic Graftcrosslinked B-II-6 30 resin particles B-II-9 30 composition (B-II)formulation Thermoplastic resin C-II-1 70 70 (parts) (D-II) EvaluationTransparency Haze A C results

As is clear from Tables 19 to 24, the thermoplastic resin compositionsof Examples 3-1 to 3-38 were excellent in flowability. The moldedarticles obtained in Examples 3-1 to 3-38 were excellent in impactresistance, color developability, abrasion resistance, and weatherresistance. By contrast, Comparative Examples 3-1 to 3-7, which did notmeet the requirements of the third invention, were poor in any offlowability, and impact resistance, color developability, abrasionresistance, and weather resistance of the molded articles.

As shown in Table 25, the molded article of Example 3-6 was excellent intransparency, whereas the molded article of the Comparative Example 3-2was poor in transparency.

These results show that the crosslinked particles (A-II) and the graftcrosslinked particles (B-II) can improve the flowability, impactresistance, and abrasion resistance of a thermoplastic resin withoutimpairing its color developability and weather resistance and aresuitable for use in applications such as automotive interior andexterior parts, office machines, household electrical appliances, andbuilding materials.

Examples and Comparative Examples of Fourth Invention [Production ofRubbery Polymer] Synthesis Example 4-1: Production of Rubbery Polymer(A-III-1)

A rubbery polymer (A-III-1) was produced according to the followingformulation.

[Formulation] n-Butyl acrylate 100 parts Hexadecane 2.4 partsDipotassium alkenyl succinate 0.4 parts Allyl methacrylate 0.2 parts1,3-Butylene dimethacrylate 1.0 part t-Butyl hydroperoxide 0.25 partsFerrous sulfate 0.0002 parts Sodium formaldehyde sulfoxylate 0.33 partsDisodium ethylenediaminetetraacetate 0.0004 parts Distilled water 203parts

Distilled water, n-butyl acrylate, hexadecane, dipotassium alkenylsuccinate, allyl methacrylate, 1,3-butylene dimethacrylate, and t-butylhydroperoxide were loaded into a reactor equipped with a reagentinjector, a condenser, a jacket heater, and a stirring device, andultrasonication was performed at an amplitude of 35 μm for 20 minutesusing an ULTRASONIC HOMOGENIZER US-600 available from Nihonseiki KaishaLtd. at normal temperature to obtain a pre-emulsion (a-III-1). Theaverage particle size of the latex obtained was 180 nm.

After the pre-emulsion (a-III-1) was heated to 60° C., ferrous sulfate,sodium formaldehyde sulfoxylate, and disodiumethylenediaminetetraacetate were added to initiate radicalpolymerization. The polymerization of the acrylate components caused theliquid temperature to rise to 78° C. The temperature was maintained at70° C. for 30 minutes, and the polymerization of the acrylate componentswas completed to obtain a rubbery polymer (A-III-1). The solid contentof the rubbery polymer (A-III-1) in the latex obtained was 18.7%, andthe volume average particle size (X) was 180 nm. The volume averageparticle size, largest 10% frequency particle size (Y), and smallest 10%frequency particle size (Z) of the rubbery polymer (A-III-1) are shownin Table 26.

The average particle size and particle size distribution of the rubberypolymer (A-III-1) and rubbery polymers (A-III-2) to (A-III-12) describedbelow and the average particle size of graft copolymers (B-III-1) to(B-111-12) described below were measured by the following method.

<Measurement of Particle Size>

The volume average particle size was determined by a dynamic lightscattering method using a Nanotrac UPA-EX150 available from Nikkiso Co.,Ltd.

The particle size distribution was determined in the same manner asdescribed above. The ratio of the largest 10% frequency particle size(Y), which is a particle size at a largest 10% frequency, to the volumeaverage particle size (X) and the ratio of the smallest 10% frequencyparticle size (Z), which is a particle size at a smallest 10% frequency,to the volume average particle size (X) were calculated.

Synthesis Examples 4-2 to 4-9: Production of Rubbery Polymers (A-III-2)to (A-III-9)

Using materials shown in Table 26 in proportions shown in Table 26,synthesis was performed in the same manner as in Synthesis Example 4-1to obtain rubbery polymers (A-III-2) to (A-III-9). The volume averageparticle size (X), largest 10% frequency particle size (Y), and smallest10% frequency particle size (Z) of the rubbery polymers (A-III-2) to(A-III-9) are shown in Table 26.

Synthesis Example 4-10: Production of Rubbery Polymer (A-III-10)

A rubbery polymer (A-III-10) was produced according to the followingformulation.

[Formulation] n-Butyl acrylate 100 parts Hexadecane 2.4 partsDipotassium alkenyl succinate 1.0 part Allyl methacrylate 0.2 parts1,3-Butylene dimethacrylate 1.0 part t-Butyl hydroperoxide 0.25 partsFerrous sulfate 0.0002 parts Sodium formaldehyde sulfoxylate 0.33 partsDisodium ethylenediaminetetraacetate 0.0004 parts Distilled water 203parts

Distilled water was loaded into a reactor equipped with a reagentinjector, a condenser, a jacket heater, and a stirring device. Afterheating to 60° C., ferrous sulfate, sodium formaldehyde sulfoxylate, anddisodium ethylenediaminetetraacetate were added. A mixed solution ofn-butyl acrylate, hexadecane, dipotassium alkenyl succinate, allylmethacrylate, 1,3-butylene dimethacrylate, and t-butyl hydroperoxide wasadded dropwise with a pump over 120 minutes to raise the temperature to80° C. After completion of the dropwise addition, the temperature wasmaintained at 70° C. for 30 minutes, and the polymerization of theacrylate components was completed to obtain a rubbery polymer(A-III-10). The solid content of the rubbery polymer (A-III-10) in thelatex obtained was 18.4%, and the volume average particle size (X) was180 nm. The largest 10% frequency particle size (Y) and smallest 10%frequency particle size (Z) were as shown in Table 27.

Synthesis Example 4-11: Production of Rubbery Polymer (A-III-11)

A rubbery polymer (A-III-11) was produced according to the followingformulation.

[Formulation] n-Butyl acrylate 100 parts Hexadecane 2.4 partsDipotassium alkenyl succinate 1.0 part Allyl methacrylate 0.2 parts1,3-Butylene dimethacrylate 1.0 part t-Butyl hydroperoxide 0.25 partsFerrous sulfate 0.0002 parts Sodium formaldehyde sulfoxylate 0.33 partsDisodium ethylenediaminetetraacetate 0.0004 parts Distilled water 203parts

Distilled water, n-butyl acrylate, hexadecane, dipotassium alkenylsuccinate, allyl methacrylate, 1,3-butylene dimethacrylate, and t-butylhydroperoxide were loaded into a reactor equipped with a reagentinjector, a condenser, a jacket heater, and a stirring device. Afterheating to 60° C., ferrous sulfate, sodium formaldehyde sulfoxylate, anddisodium ethylenediaminetetraacetate were added to initiate radicalpolymerization. The polymerization of the acrylate components caused theliquid temperature to rise to 78° C. The temperature was maintained at70° C. for 30 minutes, and the polymerization of the acrylate componentswas completed to obtain a rubbery polymer. The solid content of therubbery polymer in the latex obtained was 18.4%, and the volume averageparticle size was 100 nm.

After the liquid temperature inside the reactor decreased to 70° C., 1.0part, on a solids basis, of a 5% aqueous sodium pyrophosphate solutionwas added. After the inner temperature was controlled to be 70° C., 0.3parts, on a solid basis, of an acid-radical-containing copolymer latexcontaining 15 parts of methacrylic acid was added, and stirring andenlargement were performed for 30 minutes to obtain a rubbery polymer(A-III-11). The volume average particle size (X) of the rubbery polymer(A-III-11) was 560 nm. The largest 10% frequency particle size (Y) andsmallest 10% frequency particle size (Z) were as shown in Table 27.

Synthesis Example 4-12: Production of Rubbery Polymer (A-III-12)

A rubbery polymer (A-III-12) was obtained in the same manner as inSynthesis Example 4-11 except that 3.0 parts, on a solid basis, of anaqueous sodium pyrophosphate solution was added. The volume averageparticle size (X) thereof was 950 nm. The largest 10% frequency particlesize (Y) and smallest 10% frequency particle size (Z) were as shown inTable 27.

[Production and Evaluation of Graft Copolymers]

Example 4-1: Production of Graft Copolymer (B-III-1)

Raw materials of the following formulation were loaded into a reactorequipped with a reagent injector, a condenser, a jacket heater, and astirring device, and the reactor was thoroughly purged with nitrogen,after which the inner temperature was raised to 70° C. with stirring.

[Formulation] Water (including water in rubbery 230 parts polymer latex)Rubbery polymer (A-III-1) latex 50 parts (on a solids basis) Dipotassiumalkenyl succinate 0.2 parts Sodium formaldehyde sulfoxylate 0.3 partsFerrous sulfate 0.001 parts Disodium ethylenediaminetetraacetate 0.003parts

Next, a mixed solution containing acrylonitrile (AN), styrene (ST), andt-butyl hydroperoxide according to the following formulation was addeddropwise over 100 minutes, while the temperature was raised to 80° C.

[Formulation] Acrylonitrile 12.5 parts Styrene 37.5 parts t-Butylhydroperoxide 0.2 parts

After completion of the dropwise addition, the temperature at 80° C. wasmaintained for 30 minutes and then cooled to obtain a graft copolymer(B-III-1) latex. The solid content of the graft copolymer (B-III-1) inthe latex obtained was 29.7%, and the volume average particle size was210 nm.

Next, 100 parts of a 1.5% aqueous sulfuric acid solution were heated to80° C., and while stirring the aqueous solution, 100 parts of the graftcopolymer (B-III-1) latex was gradually added dropwise to the aqueoussolution to solidify the graft copolymer (B-III-1). Furthermore, thetemperature was raised to 95° C. and maintained for 10 minutes.

Next, the solidified product was dehydrated, washed, and dried to obtainthe graft copolymer (B-III-1) in powder form.

Examples 4-2 to 4-5, Comparative Examples 4-1 to 4-3: Production ofGraft Copolymers (B-III-2) to (B-III-12)

Graft copolymers (B-III-2) to (B-III-12) were obtained in the samemanner as in Example 4-1 except that rubbery polymer (A-III-2) to(A-III-12) latexes were each used in place of the rubbery polymer(A-III-1) latex. The volume average particle size of the graftcopolymers (B-III-2) to (B-III-12) were as shown in Tables 26 and 27.

<Production of Thermoplastic Resin Composition>

Forty parts of each of the graft copolymers (B-III-1) to (B-III-12) and60 parts of an acrylonitrile-styrene copolymer (“UMG AXS resin S102N”available from UMG ABS, Ltd.) produced by suspension polymerization weremixed together using a Henschel mixer, and the mixture was fed to anextruder heated to 240° C. and kneaded to obtain pellets.

<Preparation of Test Piece>

Each of the above-described pellets was molded with a 4 ounce injectionmolding machine (available from Japan Steel Works, LTD.) under theconditions of a cylinder temperature of 240° C. and a mold temperatureof 60° C. to obtain a test piece 1 having a length of 80 mm, a width of10 mm, and a thickness of 4 mm.

In a similar manner, a plate-like molded body 2 having a length of 100mm, a width of 100 mm, and a thickness of 2 mm was obtained under theconditions of a cylinder temperature of 240° C., a mold temperature of60° C., and an injection rate of 20 g/s.

<Evaluation>

<<Measurement of Charpy Impact Strength>>

Using the test piece 1, Charpy impact strength was measured in a 23° C.atmosphere in accordance with ISO 179.

<<Measurement of Melt Volume Rate (MVR)>>

The MVR of the thermoplastic resin composition pellets was measuredunder the conditions of 220° C. and 98 N in accordance with ISO 1133standard. The MVR indicates the flowability of the thermoplastic resincompositions.

<<Measurement of Color Developability>>

The L* of a surface of the molded body 2 was measured using acolorimeter CM-508D available from Minolta. Smaller L* values indicatebetter color developability.

<<Measurement of Image Clarity>>

The image clarity (%) at a reflectance of 60° of the surface of themolded body 2 was measured with an image clarity meter (ICM-IDPavailable from Suga Test Instruments Co., Ltd). Higher image clarityvalues indicate higher brightness of a molded article surface and bettermolded appearance.

The evaluation results of the above-described measurements are shown inTables 26 and 27.

TABLE 26 Example 4-1 Example 4-2 Example 4-3 Example 4-4 Example 4-5Graft Type of graft copolymer B-III-1 B-III-2 B-III-3 B-III-4 B-III-5copolymer Rubbery polymer/AN/ST (parts) 50/12.5/37.5 50/12.5/37.550/12.5/37.5 50/12.5/37.5 50/12.5/37.5 (B-III) Volume average nm 210 310590 770 1150 particle size Rubbery Type A-III-1 A-III-2 A-III-3 A-III-4A-III-5 polymer Preparation method Miniemulsion MiniemulsionMiniemulsion Miniemulsion Miniemulsion (A-III) Hydrophobe Parts 2.4 2.42.4 2.4 2.4 Emulsifier Parts 0.40 0.20 0.10 0.06 0.04 Volume averageparticle nm 180 280 560 760 960 size (X) Largest 10% frequency nm 290390 950 1140 1730 particle size (Y) (1.6X) (1.4X) (1.7X) (1.5X) (1.8X)Smallest 10% frequency nm 130 220 340 460 480 particle size (Z) (0.72X)(0.79X) (0.60X) (0.60X) (0.50X) Evaluation Charpy impact strength kJ/m²7 10 12 13 10 results MVR cm³/10 min 11 11 10 9 10 Color developabilityL value 8.9 9.4 10.5 11.5 11.8 Image clarity % 85 82 80 78 75 Example4-6 Example 4-7 Example 4-8 Example 4-9 Graft Type of graft copolymerB-III-6 B-III-7 B-III-8 B-III-9 copolymer Rubbery polymer/AN/ST (parts)50/12.5/37.5 50/12.5/37.5 50/12.5/37.5 50/12.5/37.5 (B-III) Volumeaverage nm 310 130 880 440 particle size Rubbery Type A-III-6 A-III-7A-III-8 A-III-9 polymer Preparation method Miniemulsion MiniemulsionMiniemulsion Miniemulsion (A-III) Hydrophobe Parts 2.4 2.4 2.4 2.4Emulsifier Parts 0.22 0.70 0.05 0.15 Volume average particle nm 290 120790 350 size (X) Largest 10% frequency nm 520 190 1420 600 particle size(Y) (1.8X) (1.6X) (1.8X) (1.7X) Smallest 10% frequency nm 200 80 510 190particle size (Z) (0.70X) (0.66X) (0.64X) (0.53X) Evaluation Charpyimpact strength kJ/m² 11 5 13 10 results MVR cm³/10 min 10 11 9 11 Colordevelopability L value 11.3 8.9 12.2 11.2 Image clarity % 72 86 75 77

TABLE 27 Comparative Comparative Comparative example4-1 example4-2example4-3 Graft Type of graft copolymer B-III-10 B-III-11 B-III-12copolymer Rubbery polymer/AN/ST (parts) 50/12.5/37.5 50/12.5/37.550/12.5/37.5 (B-III) Volume average nm 200 600 1330 particle sizeRubbery Type A-III-10 A-III-11 A-III-12 polymer Preparation methodSeeding Enlargement Enlargement (A-III) Hydrophobe Parts 2.4 2.4 2.4Emulsifier Parts 1.00 1.00 1.00 Volume average particle nm 180 560 950size (X) Largest 10% frequency nm 320 (1.8X)  1060 (1.9X)  1810 (1.9X) particle size (Y) Smallest 10% frequency nm 110 (0.61X) 280 (0.50X) 380(0.40X) particle size (Z) Evaluation Charpy impact strength kJ/m² 4 9 12results MVR cm³/10 min 10 10 10 Color developability L value 9.6 13.417.8 Image clarity % 82 70 65

The results of Examples and Comparative Examples revealed the following.

The thermoplastic resin compositions of Examples 4-1 to 4-9 areexcellent in impact resistance, color developability, and moldedappearance.

By contrast, the thermoplastic resin compositions of ComparativeExamples 4-1 to 4-3 were poor in any of impact resistance, colordevelopability, and molded appearance. Specifically, in ComparativeExample 4-1, impact resistance is poor because the rubbery polymer(A-III-10) is a seeded polymerization product. In Comparative Example4-2, color developability and molded appearance are poor because therubbery polymer (A-III-11) is an enlargement polymerization product andhas a wide particle size distribution. In Comparative Example 4-3, colordevelopability and molded appearance are poor because the rubberypolymer (A-III-12) is an enlargement polymerization product and has awide particle size distribution and low polymerization stability.

INDUSTRIAL APPLICABILITY

The thermoplastic resin composition of the first invention and moldedarticles thereof are excellent in weather resistance, colordevelopability, and also impact resistance and thus is suitable forlong-term outdoor use such as vehicles and building materials.

Thermoplastic resin molded articles including the crosslinked particles(A-I) and/or the graft crosslinked particles (B-I) of the secondinvention are useful as vehicle interior and exterior parts, officemachines, household electrical appliances, building materials, etc.

Thermoplastic resin molded articles including the crosslinked particles(A-II) and/or the graft crosslinked particles (B-II) of the thirdinvention are useful as vehicle interior and exterior parts, officemachines, household electrical appliances, building materials, etc.

Molded articles made of the thermoplastic resin composition of thefourth invention including the graft copolymer (B-III) of the thirdinvention obtained using the rubbery polymer (A-III) of the fourthinvention are good in impact resistance, color developability, andmolded appearance. This balance of impact resistance, colordevelopability, and molded appearance is very excellent as compared tomolded articles made of conventional thermoplastic resin compositions,and thus the thermoplastic resin composition of the fourth invention andmolded articles thereof are extremely useful as various industrialmaterials.

Although the present invention has been described in detail by using aspecific embodiment, it should be apparent to those skilled in the artthat various modifications can be made without departing from the spiritand the scope of the present invention.

This application is based on Japanese Patent Application No. 2015-212024filed on Oct. 28, 2015, Japanese Patent Application No. 2015-212025filed on the same date, Japanese Patent Application No. 2015-212026filed on the same date, and Japanese Patent Application No. 2015-212027filed on the same date, which are incorporated by reference herein intheir entirety.

1. A graft copolymer (C) obtained by graft-polymerizing one or two ormore monomers (B), which are selected from (meth)acrylic acid esters,aromatic vinyls, vinyl cyanides, N-substituted maleimides, and maleicacid, onto a composite rubber-like polymer (A), which is obtained bypolymerizing a mixture (Ac) containing a polyorganosiloxane (Aa) and anacrylic acid ester (Ab) after forming a miniemulsion in water solvent.2. (canceled)
 3. (canceled)
 4. (canceled)
 5. A thermoplastic resincomposition comprising: the graft copolymer (C) according to claim 1;and a thermoplastic resin (D).
 6. (canceled)
 7. A molded articleobtained by molding the thermoplastic resin composition according toclaim
 5. 8. Crosslinked particles (A-I) obtained by polymerizing amonomer mixture (i-I) containing a di(meth)acrylic acid ester (a) havinga number average molecular weight (Mn) of 800 to 9,000 and representedby formula (1):

wherein X represents a divalent residue constituted by at least one diolselected from polyalkylene glycols, polyester diols, and polycarbonatediols, and R^(1a) and R^(1b) each independently represent H or CH₃. 9.(canceled)
 10. (canceled)
 11. The crosslinked particles (A-I) accordingto claim 8, wherein the monomer mixture (i-I) contains thedi(meth)acrylic acid ester (a), an aromatic vinyl (b), and a vinylcyanide (c), and a proportion of the aromatic vinyl (b) in 100% by massof a total of the aromatic vinyl (b) and the vinyl cyanide (c) is 60% to90% by mass.
 12. (canceled)
 13. (canceled)
 14. Graft crosslinkedparticles (B-I) obtained by graft-polymerizing a monomer onto thecrosslinked particles (A-I) according to claim
 8. 15. (canceled) 16.(canceled)
 17. A thermoplastic resin composition comprising: thecrosslinked particles (A-I) according to claim 8 and a thermoplasticresin (D-I).
 18. A molded article obtained by molding the thermoplasticresin composition according to claim
 17. 19. Crosslinked particles(A-II) having a volume average particle size of 0.07 to 2.0 μm andobtained by polymerizing a monomer mixture (i-II) containing adi(meth)acrylic acid ester (a) and a mono(meth)acrylic acid component(d), wherein a content of the di(meth)acrylic acid ester (a) in 100% bymass of the monomer mixture (i-II) is 20% to 80% by mass, thedi(meth)acrylic acid ester (a) having a number average molecular weightof 800 to 9,000 and being represented by formula (1):

wherein X represents a divalent residue constituted by at least one diolselected from polyalkylene glycols, polyester diols, and polycarbonatediols, and R^(1a) and R^(1b) each independently represent H or CH₃. 20.(canceled)
 21. (canceled)
 22. (canceled)
 23. (canceled)
 24. Graftcrosslinked particles (B-II) obtained by graft-polymerizing one or moremonomers selected from (meth)acrylic acid esters, aromatic vinyls, vinylcyanides, maleimides, and maleic anhydride onto the crosslinkedparticles (A-II) according to claim
 19. 25. (canceled)
 26. (canceled)27. A thermoplastic resin composition comprising: the crosslinkedparticles (A-II) according to claim 19 and a thermoplastic resin (D-II).28. A molded article obtained by molding the thermoplastic resincomposition according to claim
 27. 29. A rubbery polymer (A-III) that isa miniemulsion polymerization reaction product of an alkyl(meth)acrylate.
 30. The rubbery polymer (A-III) according to claim 29,wherein the rubbery polymer (A-III) is a miniemulsion polymerizationreaction product of a mixture (i-III) containing an alkyl(meth)acrylate, a hydrophobe, and an emulsifier.
 31. (canceled) 32.(canceled)
 33. A graft copolymer (B-III) comprising: the rubbery polymer(A-III) according to claim 29; and at least one monomer selected fromaromatic vinyl compounds, (meth)acrylic acid esters, and vinyl cyanidecompounds graft-polymerized onto the rubbery polymer (A-III). 34.(canceled)
 35. (canceled)
 36. A thermoplastic resin compositioncomprising the graft copolymer (B-III) according to claim
 33. 37. Amolded article obtained by molding the thermoplastic resin compositionaccording to claim
 36. 38. A graft crosslinked particles (B-I) accordingto claim 14; and a thermoplastic resin (D-I).
 39. A graft crosslinkedparticles (B-II) according to claim 24; and a thermoplastic resin(D-II).